T-Mobile USA, Inc., a Delaware corporation (“T-Mobile USA” or the “Issuer”) and a direct wholly-owned subsidiary of T-Mobile US, Inc., a Delaware corporation (“T-Mobile US” or “Parent”) is offering $1,000,000,000 aggregate principal amount of its 2.250% Senior Notes due 2026 (the “2026 Notes”), $1,000,000,000 aggregate principal amount of its 2.625% Senior Notes due 2029 (the “2029 Notes”) and $1,000,000,000 aggregate principal amount of its 2.875% Senior Notes due 2031 (the “2031 Notes”). In this prospectus supplement, the term “Notes” collectively refers to the 2026 Notes, the 2029 Notes and the 2031 Notes.

We intend to use the net proceeds from this offering for general corporate purposes, which may include among other things, financing acquisitions of additional spectrum and refinancing existing indebtedness on an ongoing basis. See “Use of Proceeds.”

The 2026 Notes will bear interest at a rate of 2.250% per year and mature on February 15, 2026. The 2029 Notes will bear interest at a rate of 2.625% per year and mature on February 15, 2029. The 2031 Notes will bear interest at a rate of 2.875% per year and mature on February 15, 2031. Interest on the Notes will be paid on each February 15 and August 15, commencing August 15, 2021. See “Description of Notes—Brief Description of the Notes and the Note Guarantees—Principal, Maturity and Interest.” There is no sinking fund for the Notes.

The 2026 Notes will be redeemable, in whole or in part, at any time on or after February 15, 2023 at the redemption prices specified under “Description of Notes—Optional Redemption” plus accrued and unpaid interest to, but not including, the redemption date. The Issuer may redeem up to 40% of the aggregate principal amount of the 2026 Notes prior to February 15, 2023 with an amount equal to the net cash proceeds from certain equity offerings. The Issuer also may redeem the 2026 Notes prior to February 15, 2023 at a specified “make-whole” redemption price plus accrued and unpaid interest to, but not including, the redemption date.

The 2029 Notes will be redeemable, in whole or in part, at any time on or after February 15, 2024 at the redemption prices specified under “Description of Notes—Optional Redemption” plus accrued and unpaid interest to, but not including, the redemption date. The Issuer may redeem up to 40% of the aggregate principal amount of the 2029 Notes prior to February 15, 2024 with an amount equal to the net cash proceeds from certain equity offerings. The Issuer also may redeem the 2029 Notes prior to February 15, 2024 at a specified “make-whole” redemption price plus accrued and unpaid interest to, but not including, the redemption date.

The 2031 Notes will be redeemable, in whole or in part, at any time on or after February 15, 2026 at the redemption prices specified under “Description of Notes—Optional Redemption” plus accrued and unpaid interest to, but not including, the redemption date. The Issuer may redeem up to 40% of the aggregate principal amount of the 2031 Notes prior to February 15, 2024 with an amount equal to the net cash proceeds from certain equity offerings. The Issuer also may redeem the 2031 Notes prior to February 15, 2026 at a specified “make-whole” redemption price plus accrued and unpaid interest to, but not including, the redemption date.

If the Issuer experiences a Change of Control Triggering Event (as defined herein), the Issuer will be required to offer to repurchase the Notes at a repurchase price equal to 101% of the principal amount, plus accrued and unpaid interest to, but not including, the repurchase date. See “Description of Notes—Repurchase at the Option of Holders—Change of Control Triggering Event.”

The Issuer’s obligations under the Notes will be guaranteed (such guarantees, the “Guarantees”) by (x) T-Mobile US and each wholly-owned subsidiary of the Issuer that is not an Excluded Subsidiary (as defined herein) and either (i) is or becomes an obligor of the Credit Agreement (as defined herein) or (ii) issues or guarantees certain capital markets debt securities, and (y) any future direct or indirect subsidiary of T-Mobile US or any subsidiary thereof that owns capital stock of the Issuer.

The Notes and the Guarantees will be the Issuer’s and the guarantors’ unsubordinated unsecured obligations; will be senior in right of payment to any future indebtedness of the Issuer or any guarantor to the extent that such future indebtedness provides by its terms that it is subordinated in right of payment to the Notes and the Guarantees; will be equal in right of payment with any of the Issuer’s and the guarantors’ existing and future indebtedness and other liabilities that are not by their terms subordinated in right of payment to the Notes, including, without limitation, obligations under the Existing T-Mobile Secured Notes, the Existing T-Mobile Unsecured Notes, the Existing Sprint Unsecured Notes, the Credit Agreement and the Tower Obligations (each as defined herein); will be effectively subordinated to all existing and future secured indebtedness of the Issuer or any guarantor, including, without limitation, obligations under the Existing T-Mobile Secured Notes and the Credit Agreement, in each case to the extent of the value of the assets securing such indebtedness; and will be structurally subordinated to all of the liabilities and other obligations of the subsidiaries of T-Mobile US that are not obligors with respect to the Notes, including the Existing Sprint Spectrum-Backed Notes (as defined herein), factoring arrangements and Tower Obligations.

Investing in the Notes involves risks. See “Risk Factors” beginning on page S-17 of this prospectus supplement. You should also consider the risk factors described in the documents incorporated by reference in the accompanying prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

Each series of Notes will be issued only in registered form in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof. The Issuer does not intend to apply for the Notes to be listed on any securities exchange or to arrange for the Notes to be quoted on any quotation system. Currently, there is no public market for the Notes.

The underwriters are offering the Notes as set forth under “Underwriting.” Delivery of the Notes is expected to be made on or about January 14, 2021 through the facilities of The Depository Trust Company.

Neither we nor the underwriters named under “Underwriting” in this prospectus supplement (the “underwriters”) have authorized any other person to provide you with information different from that contained in or incorporated by reference in this prospectus supplement and the accompanying prospectus or in any related free writing prospectus that we may provide to you. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give. We are offering to sell and are seeking offers to buy the Notes only in jurisdictions where offers and sales are permitted. The information contained in or incorporated by reference in this prospectus supplement, the accompanying prospectus and any related free writing prospectus is accurate only as of the respective dates of such documents regardless of the time of delivery of this prospectus supplement, the accompanying prospectus, any related free writing prospectus or any sale of the Notes. Our business, financial condition, results of operations and prospects may have changed since such date.

This document is in two parts. The first part is this prospectus supplement, which describes the specific terms of this offering of the Notes and also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference in this prospectus supplement and the accompanying prospectus. The second part is the accompanying prospectus, which gives more general information. Generally, when we refer to this prospectus, we are referring to both parts of this document combined. To the extent there is a conflict between the information contained in the accompanying prospectus and this prospectus supplement, you should rely on the information in this prospectus supplement; provided that if any statement in one of these documents is inconsistent with a statement in another document having a later date—for example, a document incorporated by reference in the accompanying prospectus or this prospectus supplement—the statement in the document having the later date modifies or supersedes the earlier statement.

As permitted by the rules and regulations of the Securities and Exchange Commission (the “SEC”), the registration statement of which the accompanying prospectus forms a part includes additional information not contained in this prospectus supplement. You may read the registration statement and the other reports we file with the SEC at the SEC’s website described below under the heading “Where You Can Find More Information.”

You should read this prospectus supplement along with the accompanying prospectus, any related free writing prospectus and the documents incorporated by reference carefully before you decide whether to invest. These documents contain important information you should consider when making your investment decision. This prospectus supplement contains information about the securities offered in this offering and may add, update or change information in the accompanying prospectus.

In this prospectus supplement, unless stated otherwise or the context indicates otherwise, references to “T-Mobile,” the “Company,” “our Company,” “we,” “our,” “ours” and “us” refer to T-Mobile US, Inc. together with its direct and indirect domestic subsidiaries, including T-Mobile USA and its subsidiaries and, on and after April 1, 2020, Sprint Corporation, a Delaware corporation (“Sprint”) and its subsidiaries. References to “T-Mobile USA” and the “Issuer” refer to T-Mobile USA, Inc. only. T-Mobile USA’s corporate parent is T-Mobile US, Inc., which we refer to in this prospectus supplement on a stand-alone basis as “T-Mobile US” or “Parent.” T-Mobile US has no operations separate from its investment in T-Mobile USA. Accordingly, unless otherwise noted, all of the business and financial information in this prospectus supplement, including the factors identified under “Risk Factors” beginning on page S-17, is presented on a consolidated basis for T-Mobile.

On April 29, 2018, Parent entered into a Business Combination Agreement (as amended and supplemented, the “Business Combination Agreement”) with Sprint, Huron Merger Sub LLC, a Delaware limited liability company and a wholly owned subsidiary of Parent (“T-Mobile Merger Company”), Superior Merger Sub Corporation, a Delaware corporation and a wholly owned subsidiary of T-Mobile Merger Company (“Merger Sub”), Starburst I, Inc., a Delaware corporation (“Starburst”), Galaxy Investment Holdings, Inc., a Delaware corporation (“Galaxy,” and together with Starburst, the “SoftBank US HoldCos”), and for the limited purposes set forth therein, Deutsche Telekom AG, an Aktiengesellschaft organized and existing under the laws of the Federal Republic of Germany (“Deutsche Telekom”), Deutsche Telekom Holding B.V., a besloten vennootschap met beperkte aansprakelijkheid organized and existing under the laws of the Netherlands (“DT Holding”) and SoftBank Group Corp., a Japanese kabushiki kaisha (“SoftBank”). In this prospectus supplement, references to the “combined company” refer to the combined businesses of T-Mobile US and its subsidiaries and Sprint and its subsidiaries following consummation of the BCA Transactions. On April 1, 2020, pursuant to the Business Combination Agreement and upon the terms and subject to the conditions described therein: (a) each of Galaxy and Starburst merged with and into T-Mobile Merger Company, with T-Mobile Merger Company continuing as the surviving entity and as a wholly owned subsidiary of T-Mobile US (the “HoldCo Mergers”); and (b) Merger Sub merged with and into Sprint, with Sprint continuing as the surviving corporation and as a wholly owned indirect subsidiary of T-Mobile US (the “Merger” and collectively with the HoldCo Mergers, the “BCA Transactions”). Promptly following the consummation of the Merger, T-Mobile US contributed Sprint to T-Mobile USA, causing Sprint to become a wholly owned subsidiary of T-Mobile USA (the “Contribution”).

The T-Mobile Debt Repayments (as defined below) and the Sprint Debt Repayments (as defined below) were financed by borrowings under (x) the Bridge Term Loan Credit Agreement, dated as of April 1, 2020 (the “Bridge Credit Agreement”), by and among T-Mobile USA, as borrower, Goldman Sachs Bank USA, as administrative agent, and the lenders and other financial institutions party thereto, providing $19.0 billion of

bridge loans, and (y) the Credit Agreement (as defined under “Description of Other Indebtedness and Certain Financing Transactions—Credit Agreement”), providing a $4.0 billion Term Loan Facility (as defined under “Description of Other Indebtedness and Certain Financing Transactions—Credit Agreement”), and a $4.0 billion revolving credit facility. In connection with the BCA Transactions, (i) (a) we repaid the outstanding amounts under and terminated our $4.0 billion secured term loan facility under the Term Loan Credit Agreement, dated November 9, 2015, among T-Mobile USA, as borrower, the Company, as a guarantor, the other guarantors party thereto, Deutsche Bank AG New York Branch (“DB”), as administrative agent, and Deutsche Telekom, as lender, as amended (the “2015 T-Mobile Secured Term Loan Facility”) with no prepayment premium or penalty and (b) we terminated our three-year $1.0 billion senior unsecured revolving credit agreement with Deutsche Telekom, as administrative agent and lender (the “2016 T-Mobile Unsecured Revolving Credit Facility”) and our three-year $1.5 billion senior secured revolving credit agreement with Deutsche Telekom, as administrative agent, collateral agent and lender (the “2016 T-Mobile Secured Revolving Credit Facility,” and together with the 2016 T-Mobile Unsecured Revolving Credit Facility, the “2016 T-Mobile Revolving Credit Facilities”) with no prepayment premium or penalty and (c) we repurchased, at par plus accrued and unpaid interest, our 5.300% Notes due 2021 and 6.000% Notes due 2024, the amounts outstanding under which facilities and notes were owed to Deutsche Telekom (the items in this clause (i) being referred to collectively as the “T-Mobile Debt Repayments”), (ii) (a) we repaid the outstanding amounts under the Credit Agreement, dated as of February 3, 2017, as amended, by and among Sprint Communications, Inc., as borrower, the guarantors party thereto, JPMorgan Chase Bank, N.A., as administrative agent, and the lenders party thereto (the “Sprint Secured Term Loan Facility”), (b) we repaid the amounts outstanding under the Third Amended and Restated Receivables Purchase Agreement, dated as of June 29, 2018, as amended, by and among Sprint Spectrum L.P., as servicer, certain Sprint special purpose entities, as sellers, and financial institutions from time to time party thereto (the “Sprint Accounts Receivable Facility”), (c) we redeemed the 7.250% Guaranteed Notes due 2028 of Sprint and (d) we repaid certain other indebtedness of Sprint and its subsidiaries (the items in this clause (ii) being referred to collectively as the “Sprint Debt Repayments”) and (iii) the maturity dates applicable to our 5.125% Senior Notes due 2025-1 and 5.375% Senior Notes due 2027-1 were amended from April 15, 2025 to April 15, 2021 and from April 15, 2027 to April 15, 2022, respectively (the “T-Mobile Maturity Amendments”). As a result of the BCA Transactions, (i) T-Mobile US and T-Mobile USA have guaranteed on an unsecured basis the obligations under the Existing Sprint Unsecured Notes (as defined under “Description of Other Indebtedness and Certain Financing Transactions—Existing Sprint Unsecured Notes” and such guarantees, collectively with the guarantees of the Existing Sprint Spectrum Lease (as defined under “Description of Other Indebtedness and Certain Financing Transactions—Existing Sprint Spectrum Note Facility”), the “Sprint Debt Assumptions”), (ii) T-Mobile US and T-Mobile USA and the wholly-owned domestic subsidiaries of the Issuer that became obligors of the Credit Agreement have guaranteed on a secured basis (with such security capped at $3.5 billion) the lease payment obligations under the Existing Sprint Spectrum Lease and (iii) Sprint and its wholly-owned domestic subsidiaries that will guarantee the Notes have also guaranteed on an unsecured basis the obligations under the Existing T-Mobile Unsecured Notes (as defined under “Description of Other Indebtedness and Certain Financing Transactions—Existing T-Mobile Unsecured Notes”).

On April 9, 2020, all $19.0 billion of borrowings outstanding under the Bridge Credit Agreement were repaid in full with the net proceeds of the offering of $19.0 billion of Existing T-Mobile Secured Notes (as defined under “Description of Other Indebtedness and Certain Financing Transactions—Existing T-Mobile Secured Notes”), together with cash on hand (the entry into and borrowings under the Bridge Credit Agreement and the Credit Agreement, the issuance of $19.0 billion of Existing T-Mobile Secured Notes on April 9, 2020 and the repayment of outstanding amounts under the Bridge Credit Agreement with the proceeds of such Existing T-Mobile Secured Notes, the “T-Mobile Financing Transactions”). We refer to the Merger, the BCA Transactions, the Contribution, the T-Mobile Financing Transactions (including the issuance of $19.0 billion of Existing T-Mobile Secured Notes on April 9, 2020 and the repayment of amounts under the Bridge Credit Agreement in connection therewith), the T-Mobile Debt Repayments, the Sprint Debt Repayments, the Sprint Debt Assumptions, and the T-Mobile Maturity Amendments collectively as the “Transactions.”

On September 16, 2020, T-Mobile USA increased the aggregate commitment under the revolving credit facility to $5.5 billion through an amendment to the Credit Agreement, with proceeds from draws thereunder to be used for general corporate purposes including working capital needs. On October 9, 2020, all $4.0 billion of

borrowings outstanding under the Term Loan Facility were repaid in full. See “Description of Other Indebtedness and Certain Financing Transactions—Existing T-Mobile Secured Notes” and “Description of Other Indebtedness and Certain Financing Transactions—Credit Agreement.”

Market data and other statistical information used in this prospectus supplement, the accompanying prospectus or any related free writing prospectus or incorporated by reference in this prospectus supplement, the accompanying prospectus or any related free writing prospectus are based on independent industry publications, government publications, reports by market research firms and other published independent sources. Some data is also based on our good faith estimates, which we derive from our review of internal surveys and independent sources. Although we believe these sources are reliable, we have not independently verified the information. We neither guarantee its accuracy nor undertake a duty to provide or update such data in the future.

This prospectus supplement, the accompanying prospectus, any related free writing prospectus and the documents incorporated by reference in this prospectus supplement, the accompanying prospectus or any related free writing prospectus may include trademarks, trade names and service marks owned by us or other companies. All trademarks, trade names and service marks included or incorporated by reference in this prospectus supplement, the accompanying prospectus, any related free writing prospectus and the documents incorporated by reference in this prospectus supplement, the accompanying prospectus or any related free writing prospectus are the property of their respective owners.

Certain numbers and percentages presented in this prospectus supplement may not sum to the totals presented due to rounding.

Certain statements in this prospectus supplement, the accompanying prospectus, any related free writing prospectus, the documents incorporated by reference and our other public statements include “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. All statements, other than statements of historical fact, including information concerning our future results of operations, are forward-looking statements. These forward-looking statements are generally identified by the words “anticipate,” “believe,” “estimate,” “expect,” “intend,” “may,” “could” or similar expressions. Forward-looking statements are based on current expectations and assumptions, which are subject to risks and uncertainties that may cause actual results to differ materially from the forward-looking statements. The following important factors, along with the factors identified under “Risk Factors” and the risk factors incorporated by reference herein, could affect future results and cause those results to differ materially from those expressed in the forward-looking statements:

Additional information concerning these and other risk factors is contained in the section titled “Risk Factors” in this prospectus supplement and the documents incorporated by reference.

Forward-looking statements in this prospectus supplement, the accompanying prospectus, any related free writing prospectus or the documents incorporated by reference speak only as of the date of this prospectus supplement or the applicable document incorporated by reference (or such earlier date as may be specified in the applicable document), as applicable, are based on assumptions and expectations as of such dates, and involve risks, uncertainties and assumptions, many of which are beyond our ability to control or predict, including the factors above. Given these risks and uncertainties, readers are cautioned not to place undue reliance on such forward-looking statements. We undertake no obligation to revise or publicly release any revision to these forward-looking statements, except as required by law. For more information, see the section entitled “Where You Can Find More Information.” The results presented for any period may not be reflective of results for any subsequent period.

You should carefully read and consider the cautionary statements contained or referred to in this section in connection with any subsequent written or oral forward-looking statements that may be issued by us or persons acting on our behalf, and all future written and oral forward-looking statements attributable to us are expressly qualified in their entirety by the foregoing cautionary statements.

An investment in the Notes involves a high degree of risk. Prior to making a decision about investing in the Notes, you should carefully consider the following risks and uncertainties, as well as those discussed under the caption “Risk Factors” in Parent’s Quarterly Reports on Form 10-Q for the quarters ended March 31, 2020, June 30, 2020 and September 30, 2020 filed with the SEC on May 6, 2020, August 6, 2020 (as amended by Amendment No. 1 to such Quarterly Report on Form 10-Q filed on August 10, 2020) and November 5, 2020, respectively. If any of the risks described in this prospectus supplement, the accompanying prospectus or any related free writing prospectus, or the risks described in any documents incorporated by reference in this prospectus supplement, the accompanying prospectus or any related free writing prospectus, actually occur, our business, prospects, financial condition or operating results could be harmed. In such case, the trading price of the Notes could decline, and you may lose all or part of your investment.

The pro forma financial information incorporated by reference in this prospectus supplement is presented for illustrative purposes only and may not be an accurate indication of what results of operations would have been had the BCA Transactions been completed on the dates assumed. The pro forma financial information has been derived from the audited and unaudited historical financial statements of T-Mobile and Sprint, and certain adjustments and assumptions have been made regarding T-Mobile after giving effect to the Transactions. The pro forma financial statements do not include, among other things, estimated cost or growth synergies, adjustments related to restructuring or integration activities, future acquisitions or disposals not yet known or probable, including those that may be required by regulatory or governmental authorities in connection with the BCA Transactions, impacts of merger-related change in control provisions that are currently not factually supportable and/or probable of occurring, or the issuance of the Notes. The preliminary allocation of the purchase price to the acquired assets and assumed liabilities of Sprint was based on the estimate of fair value. For the preliminary fair values of the assets acquired and liabilities assumed, we used the cost, income and market approaches, including market participant assumptions. The unaudited pro forma adjustments are based upon available information and certain assumptions that T-Mobile believes are reasonable under the circumstances. Actual results may differ materially from the assumptions within the accompanying unaudited pro forma condensed combined financial information. The purchase adjustments relating to the Sprint and T-Mobile combined financial information are preliminary and subject to change as additional analyses are performed and finalized.

In addition, the assumptions used in preparing the pro forma financial information may not prove to be accurate. Such assumptions can be adversely affected by known or unknown facts, risks and uncertainties, many of which are beyond our control. Other factors may also affect our financial condition or results of operations. In view of these uncertainties, the inclusion and incorporation by reference of pro forma financial information in this prospectus supplement is for illustrative purposes and does not purport to project the future consolidated results of operations or consolidated financial condition for any future period or as of any future date. See the unaudited pro forma condensed combined financial information and related notes filed as Exhibit 99.1 to Parent’s Current Report on Form 8-K filed on September 18, 2020.

We have, and we expect that we will continue to have, a significant amount of debt. Assuming that on September 30, 2020, we had completed the Q4 Prepayment and the Q4 Notes Issuances, and also completed this offering, we would have had approximately $80.0 billion of outstanding indebtedness and other obligations, excluding letter of credit obligations, including $36.6 billion of effectively senior outstanding secured indebtedness and $38.9 billion of pari passu outstanding unsecured indebtedness. Our effectively senior, secured indebtedness would consist of $31.8 billion of Existing T-Mobile Secured Notes and an aggregate principal amount of $4.8 billion of Existing Sprint Spectrum-Backed Notes outstanding, with up to $2.2 billion remaining available for issuance, under the Sprint Spectrum Note Facility. Our pari passu unsecured indebtedness would consist of $3.0 billion of Notes offered hereby, $13.1 billion of Existing T-Mobile Unsecured Notes, $19.8 billion

of Existing Sprint Unsecured Notes, and approximately $3.1 billion in unsecured Tower Obligations. We also would have had $5.5 billion of revolving borrowings available on an effectively senior secured basis under the Credit Agreement.

Our ability to make payments on our debt, to repay our indebtedness when due and to fund our capital intensive business and operations and significant planned capital expenditures will depend on our ability to generate cash in the future. There can be no assurance that sufficient funds will be available to us under our borrowings or otherwise. Our ability to produce cash from operations is subject to a number of risks, including:

Our debt service obligations could have important material consequences to you, including the following:

Any of these risks could impair our ability to fund our operations or limit our ability to obtain additional spectrum, or expand our business as planned, which could have a material adverse effect on our business, financial condition and operating results. Any such risks could also have an adverse effect on the trading prices of the Notes.

To the extent we become party to any hedging arrangements, we may be exposed to credit-related losses in the event of nonperformance by counterparties to such hedging agreements. The primary credit exposure that we have with respect to such hedging agreements is that a counterparty will default on payments due, which could result in us having to acquire a replacement derivative from a different counterparty at a higher cost or we may be unable to find a suitable replacement. Although counterparties to any hedging agreements may be major financial institutions we would still be exposed to credit risk with these institutions. In addition, any netting and/or set off rights we may have through master netting arrangements with these counterparties may not apply to affiliates of a counterparty with whom we may have various other financial arrangements. If any financial institutions that are parties to any hedging agreements with us were to default on their payment obligations to us, declare bankruptcy or become insolvent, we may be unhedged against the underlying exposures. Any of these risks could have a material adverse effect on our business, financial condition and operating results. Additionally,

if the counterparties’ and our obligations under any hedging agreements are required to be secured by cash or U.S. Treasury securities, any posting of collateral by us under such arrangements would negatively impact our liquidity. The modification or termination of any such hedging agreements could also negatively impact our liquidity or other financial metrics.

Some of our debt also has a floating rate of interest linked to various indices. If changes in the indices result in interest rate increases, debt service requirements will increase, which could adversely affect our cash flow and operating results.

In addition, any agreements we have and may continue to enter into to limit our exposure to interest rate increases may not offer complete protection from this risk, and any portion of our indebtedness not subject to such agreements would have full exposure to interest rate increases.

Any of these risks could have a material adverse effect on our business, financial condition and operating results.

Although we have substantial indebtedness, we may still be able to incur significantly more debt, including more secured debt, as market conditions and contractual obligations permit, which could further reduce the cash available to us to invest in operations, as a result of increased debt service obligations. The terms of the agreements governing our long-term indebtedness allow for the incurrence of additional indebtedness by us and our subsidiaries, subject to specified limitations. In particular, as of December 31, 2020, we had $5.5 billion available for borrowings under the Revolving Credit Facility (as defined under “Description of Other Indebtedness and Certain Financing Transactions—Credit Agreement”). There can be no assurance that sufficient funds will be available to us under our existing indebtedness or otherwise. The more leveraged we become, the more we, and in turn the holders of our securities, become exposed to the risks described above in the risk factor entitled “Our significant indebtedness could adversely affect our business, financial condition and operating results, and senior creditors would have a secured claim to any collateral securing the debt owed to them.”

The Notes and the Guarantees will be general unsecured, unsubordinated obligations ranking effectively junior in right of payment to all existing and future secured debt of Parent, the Issuer and of each Subsidiary Guarantor, including the Existing T-Mobile Secured Notes and borrowings under the Credit Agreement, to the extent of the value of the collateral securing such debt. The Notes also will permit us to incur certain additional secured debt.

If the Issuer or a guarantor is declared bankrupt, becomes insolvent or is liquidated or reorganized, any secured debt of the Issuer or that guarantor, including under the Existing T-Mobile Secured Notes and the Credit Agreement, will be entitled to be paid in full from the assets of the Issuer or guarantor, as applicable, securing that debt before any payment may be made with respect to Notes or the Guarantees of such guarantor.

Holders of the Notes will participate ratably in any remaining assets with all other holders of the Issuer’s and the guarantors’ unsecured obligations that are not by their terms subordinated to the Notes, based upon the respective amounts owed. In any of the foregoing events, there may not be sufficient assets to pay the indebtedness and other obligations owed to secured creditors and the amounts due on the Notes. As a result, holders of the Notes would likely receive less, ratably, than holders of secured obligations of the Issuer and the guarantors. It is possible that with respect to the Guarantees, there will be no assets from which claims of holders of the Notes can be satisfied.

The Notes and the Guarantees will be structurally subordinated to any existing or future liabilities and other obligations of the Issuer’s or the guarantors’ non-guarantor subsidiaries, including the Existing Sprint Spectrum-Backed Notes, factoring arrangements and tower obligations. Accordingly, creditors of current and

future subsidiaries of the Issuer or the guarantors that are not obligors with respect to the Notes would have claims with respect to the assets of those subsidiaries that would rank structurally senior to the Notes and the Guarantees. In the event of any distribution or payment of assets of such subsidiaries in any dissolution, winding up, liquidation, reorganization or other bankruptcy proceeding, the claims of those creditors would have to be satisfied prior to making any such distribution or payment to the Issuer or the applicable guarantor in respect of direct or indirect equity interests in such subsidiaries. Certain subsidiaries of the Issuer that are prohibited from providing guarantees of the Notes (such as special purpose finance entities and a reinsurance subsidiary), as well as non-wholly owned and immaterial subsidiaries will not provide guarantees of the Notes. Assuming that on September 30, 2020, we had completed the Q4 Prepayment and the Q4 Notes Issuances and all the Guarantees were in place, subsidiaries that will not provide guarantees of the Notes that were included in Parent’s consolidated financial statements as of such date had approximately $10.2 billion of total assets and approximately $7.0 billion in indebtedness and Tower Obligations outstanding. See “Description of Notes—Brief Description of the Notes and the Note Guarantees—The Note Guarantees.”

Our ability to meet existing or future debt obligations and to reduce indebtedness will depend on future performance and the other cash requirements of our businesses. Our performance, to a certain extent, is subject to general economic conditions and financial, competitive, business, political, regulatory and other factors, including third party rating agency assessments, that are beyond our control. In addition, our ability to borrow funds in the future to make payments on debt will depend on the satisfaction of covenants in the indentures governing the Notes and the Existing T-Mobile Secured Notes, the Existing T-Mobile Unsecured Notes and the Existing Sprint Unsecured Notes, the Credit Agreement, other debt agreements and other agreements we may enter into in the future. Specifically, under the Revolving Credit Facility under our Credit Agreement, we will need to maintain certain financial ratios on a quarterly basis. We cannot assure you that we will continue to generate sufficient cash flow from operations or that future equity issuances or borrowings will be available to us in an amount sufficient to enable us to satisfy financial covenants under the Credit Agreement, service our debt or repay our indebtedness in a timely manner or on favorable or commercially reasonable terms, or at all. If we are unable to satisfy financial covenants or to generate sufficient cash to timely repay our debt, our lenders could accelerate the maturity of some or all of our outstanding indebtedness. As a result, we may need to refinance all or a portion of our remaining existing indebtedness prior to its maturity. We also expect to need to refinance certain indebtedness. Disruptions in the financial markets, unfavorable rating agency assessments, the general amount of debt being refinanced at the same time, and our financial position and performance could make it more difficult to obtain debt or equity financing on favorable or commercially reasonable terms or at all. In addition, instability in the global financial markets has from time to time resulted in volatility in the capital markets. This volatility could limit our access to the credit markets, leading to higher borrowing costs or, in some cases, the inability to obtain financing on terms that are acceptable to us, or at all. Any such failure to obtain additional financing could jeopardize our ability to repay, refinance or reduce debt obligations. If we were able to obtain funds, it may not be on terms and conditions acceptable to us, which could limit or preclude our ability to pursue new opportunities, expand our service, upgrade our networks, engage in acquisitions or purchase additional spectrum, thus limiting our ability to expand our business, which could have a material adverse effect on our business, financial condition and operating results.

Further, should we need to raise additional capital, the foreign ownership restrictions mandated by the FCC, and applicable to us, could limit our ability to attract additional equity financing outside the United States.

We have in the past been the subject of inquiries or offers related to potential strategic transactions (such as an acquisition of the Company), we may be the subject of such inquires or offers in the future, and we may engage in discussions or negotiations regarding such inquiries or offers that may ultimately lead to a transaction. The indentures governing the Existing T-Mobile Secured Notes, the Existing T-Mobile Unsecured Notes, the Existing Sprint Spectrum-Backed Notes and certain of the Existing Sprint Unsecured Notes, provide, and the

indentures governing the Notes will provide, that, upon the occurrence of certain change of control triggering events, which change of control triggering events include a change of control combined with certain ratings downgrades or withdrawals as described further below, the Issuer will be required to offer to repurchase all outstanding Existing T-Mobile Secured Notes, Existing T-Mobile Unsecured Notes, all outstanding Existing Sprint Spectrum-Backed Notes, the applicable Existing Sprint Unsecured Notes and all outstanding Notes at 101% of the principal amount thereof plus accrued and unpaid interest, if any, to, but not including, the date of repurchase. See “Description of Notes—Repurchase at the Option of Holders—Change of Control Triggering Event” and “Description of Other Indebtedness and Certain Financing Transactions.” In addition, any such change of control triggering event is expected to cause an event of default under the Credit Agreement, entitling the lenders to declare all amounts outstanding thereunder to be immediately due and payable. Such a change of control would also trigger repayments with respect to our securitization transactions and capital leases. We may not have access to sufficient funds at the time of the change of control triggering event to make the required repurchases of the Notes, the Existing T-Mobile Secured Notes, the Existing T-Mobile Unsecured Notes, the Existing Sprint Spectrum-Backed Notes and the applicable Existing Sprint Unsecured Notes and to repay outstanding amounts under the Credit Agreement, or contractual restrictions may not allow such repurchases or repayments.

Not all change of control transactions would trigger these repurchase or repayment obligations. Specifically, these repurchase or repayment obligations would not be triggered unless both (i) such a transaction constitutes a “Change of Control” under the applicable indenture or credit agreement and (ii) such “Change of Control” is accompanied or followed by certain downgrades or withdrawals of the credit rating with respect to the applicable notes (in the case of any such indenture) or T-Mobile USA (in the case of the Credit Agreement). In the event that we undergo a significant corporate transaction that does not constitute a change of control triggering event, the Notes and such other obligations generally would be permitted to remain outstanding in accordance with their terms.

The failure to purchase the Notes, the Existing T-Mobile Secured Notes, the Existing T-Mobile Unsecured Notes, the Existing Sprint Spectrum-Backed Notes or the applicable Existing Sprint Unsecured Notes, as required under the respective indentures, would result in defaults under such indentures in addition to any events of default under the Credit Agreement resulting from a change of control triggering event thereunder, any of which could have material adverse consequences for us and the holders of the Notes. Any such event of default would likely trigger an event of default on other outstanding or future indebtedness.

The indentures governing the Notes, the Existing T-Mobile Secured Notes, the Existing T-Mobile Unsecured Notes and the Existing Sprint Unsecured Notes, the Credit Agreement and other financing arrangements, impose (or, in the case of the indentures governing the Notes, will impose) significant operating and financial restrictions on us. These restrictions, subject in certain cases to customary baskets, exceptions and incurrence-based ratio tests, limit our and our subsidiaries’ ability to engage in some transactions. In particular, the Credit Agreement and the indentures governing the Existing T-Mobile Unsecured Notes include, and the indentures governing the Notes will include, restrictions limiting our and our subsidiaries’ ability to:

In addition, the indentures governing the Existing T-Mobile Secured Notes, the Existing T-Mobile Unsecured Notes and Existing Sprint Unsecured Notes and the Credit Agreement limit, and the indentures governing the Notes will limit, our and our subsidiaries’ ability to:

In addition, the Revolving Credit Facility (as defined under “Description of Other Indebtedness and Certain Financing Transactions—Credit Agreement”) contains a financial maintenance covenant, requiring us to maintain a total first lien net leverage ratio at the end of each fiscal quarter of 3.30:1.00 or less. Any future debt that we incur may contain financial maintenance covenants as well. These restrictions could limit our ability to obtain debt financing, repurchase stock, refinance or pay principal on our outstanding debt, complete acquisitions for cash or debt or react to changes in our operating environment or the economy.

Any failure to comply with the restrictions of the indentures governing the Notes, the Existing T-Mobile Secured Notes, the Existing T-Mobile Unsecured Notes or the Existing Sprint Unsecured Notes, the Credit Agreement or other financing agreements may result in an event of default under these agreements, which in turn may result in defaults or acceleration of obligations under these agreements and other agreements, giving our lenders and other debt holders the right to terminate any commitments they had made to provide us with further funds and to require us to repay all amounts then outstanding. Any of these events would have a material adverse effect on our business, financial condition and operating results.

The Guarantee of a guarantor will be automatically and unconditionally released in respect of the Notes of any series:

If any such Guarantee is released, no holder of the Notes will have a claim as a creditor against the applicable guarantor, and the indebtedness and other liabilities of such former Subsidiary Guarantor will be structurally senior to the claim of any holder of the Notes. See “Description of Notes—Brief Description of the Notes and the Note Guarantees—The Note Guarantees.”

The Guarantees may be subject to review and potential avoidance under federal bankruptcy law or relevant state fraudulent conveyance laws if we or any guarantor file a petition for bankruptcy or our creditors file an involuntary petition for bankruptcy against us or any guarantor. Under these laws, if a court were to find that, at the time a guarantor incurred debt (including debt represented by the Guarantee), such guarantor:

The measure of insolvency for purposes of the foregoing considerations will vary depending upon the law of the jurisdiction that is being applied in any such proceeding, such that we cannot be certain as to the standards a court would use to determine whether or not the Issuer or the guarantors were insolvent at the relevant time or, regardless of the insolvency standard applied by the court, that such court would not determine (i) that the Issuer or a guarantor were indeed insolvent on that date, (ii) that any payments to the holders of the Notes (including under the Guarantees) did not constitute preferences, fraudulent transfers or conveyances on other grounds or (iii) whether the Notes or any Guarantees would be subordinated to the Issuer’s or any of the guarantors’ other debt. Generally, however, an entity would be considered insolvent if, at the time it incurred the debt or issued the Guarantee:

As a general matter, value is given for a transfer or an obligation if, in exchange for the transfer or obligation, property is transferred or a valid antecedent debt is secured or satisfied. A court would likely find that a guarantor did not receive “reasonably equivalent value” (or fair consideration for) its Guarantee to the extent the guarantor did not obtain a reasonably equivalent benefit directly or indirectly from the issuance of the Notes. Thus, if the Guarantees were legally challenged, any Guarantee could be subject to the claim that, since the Guarantee was incurred for the benefit of the Issuer, and only indirectly for the benefit of the guarantor, the obligations of the applicable guarantor were incurred for less than “reasonably equivalent value” (or fair consideration). Therefore, if a court were to find that the applicable guarantor was insolvent or rendered insolvent

by the incurrence of the Guarantee or one of the other conditions above (relating to the guarantor’s financial condition) were satisfied, the court could avoid the obligations under the Guarantees, subordinate them to the applicable guarantor’s other debt or take other action detrimental to the holders of the Notes.

If a Guarantee is avoided as a fraudulent conveyance, fraudulent transfer, or preference, or found to be unenforceable for any other reason, you will not have a claim against that obligor and will only be our creditor or that of any guarantor whose obligation was not set aside or found to be unenforceable. In addition, the loss of a Guarantee generally will constitute an event of default under the indentures governing the Notes, the Existing T-Mobile Secured Notes and the Existing T-Mobile Unsecured Notes and the Credit Agreement, which events of default would allow the relevant noteholders or lenders to accelerate the amounts due and payable thereunder, and we may not be able to pay any such amounts.

The indentures governing the Notes will contain a provision intended to limit each guarantor’s liability to the maximum amount that it could incur without causing the incurrence of obligations under its Guarantee to be a fraudulent transfer. This provision may not be effective (as a legal matter or otherwise) to protect the Guarantees from being avoided under fraudulent transfer law, or may eliminate the guarantor’s obligations or reduce the guarantor’s obligations to an amount that effectively makes the Guarantee worthless. In a Florida bankruptcy court decision (which was subsequently reversed by a district court on other grounds and then reinstated by the applicable circuit court of appeals), this kind of provision was found to be ineffective to protect the Guarantees.

In addition, any payment by us pursuant to the Notes or by a guarantor under a Guarantee made at a time we or such guarantor were found to be insolvent could be avoided as a preferential transfer under the U.S. Bankruptcy Code and required to be returned to us or such guarantor or to a fund for the benefit of our or such guarantor’s creditors if such payment is made to an insider within a one-year period prior to a bankruptcy filing or within 90 days for any non-insider party, and such payment would give such insider or non-insider party more than such party would have received in a distribution under the U.S. Bankruptcy Code in a hypothetical Chapter 7 case, subject to applicable defenses.

Finally, as a court of equity, the bankruptcy court may subordinate the claims in respect of the Notes or the Guarantees to other claims against us under the principle of equitable subordination if the court determines that (1) a holder of the Notes or the Guarantees engaged in some type of inequitable conduct, (2) the inequitable conduct resulted in injury to our other creditors or conferred an unfair advantage upon the holders of the Notes and (3) equitable subordination is not inconsistent with the provisions of the U.S. Bankruptcy Code.

For so long as any obligations under the Credit Agreement remain outstanding, any guarantee of the Notes may be released without action by, or consent of, any holder of the Notes, if the related guarantor is no longer a guarantor of obligations under the Credit Agreement or certain other indebtedness of the Issuer or any other guarantor (except, in each case, by or as a result of payment under such guarantee or direct obligation). See “Description of Notes—Brief Description of the Notes and the Note Guarantees—The Note Guarantees.” The lenders under the Credit Agreement will have the discretion to release the guarantees under the Credit Agreement in a variety of circumstances. You will not have a claim as a creditor against any entity that is no longer a guarantor of the Notes, and the indebtedness and other liabilities, including trade payables, whether secured or unsecured, of former guarantor subsidiaries will be structurally senior to claims of holders of the Notes.

The indentures governing the Notes will provide that many of its covenants will cease to apply to us if the Notes are rated investment grade by at least two of Moody’s, S&P and Fitch, provided at such time no default or event of default has occurred and is continuing. The indentures will further provide that these covenants will not be later reinstated in the event that the ratings of the Notes subsequently decline. These covenants restrict, among other things, our ability to pay dividends, to incur debt and to enter into certain other transactions. There can be no assurance that the Notes will ever be rated investment grade. However, termination of these covenants would allow us to engage in certain transactions that would not be permitted while these covenants were in force. See

“Description of Notes—Certain Covenants—Changes in Covenants When Notes Rated Investment Grade.” Although the indentures will continue to restrict the Issuer’s ability to create liens or other encumbrances after the Notes are rated investment grade by at least two of Moody’s, S&P and Fitch, such covenant may be modified at the Issuer’s election, following such a rating event, to restrict only the Issuer and Material Subsidiaries (as defined under “Description of the Notes—Certain Definitions”) from incurring liens on principal properties or upon capital stock or indebtedness of any Material Subsidiary that directly owns any principal property, subject to certain exceptions set forth in the indentures governing the Notes. See “Description of Notes—Certain Covenants—Liens.” In addition, at the Issuer’s election, following such a rating event, the Guarantees of the Subsidiary Guarantors may be released. See “—The Guarantees may be released upon the occurrence of certain events.”

The market price of the Notes could decline as a result of our, or existing investors’, sales of the Issuer’s debt securities in the market after this offering, or the perception that such sales could occur. These sales, or the possibility that these sales may occur, also might make it more difficult for the Issuer to sell other debt securities in the future at a time and on terms that it deems appropriate.

After giving effect to the issuance of the Notes, assuming that on September 30, 2020, we had completed the Q4 Prepayment and the Q4 Notes Issuances, we would have outstanding approximately $72.4 billion in aggregate principal amount of debt securities, maturing in 2021 through 2060, $36.6 billion of which would be senior secured debt securities and $35.8 billion of which would be senior unsecured debt securities. Deutsche Telekom, which currently controls approximately 52.4% of the common stock of Parent (on a fully diluted basis), holds approximately $4.8 billion of these debt securities, maturing in 2022 through 2028. We have on file an effective shelf registration statement with respect to these debt securities held by Deutsche Telekom and Deutsche Telekom could sell all or any portion of them at any time.

An active trading market may not exist for the Notes. Historically, the market for non-investment grade debt has been subject to disruptions that have caused substantial volatility in the prices of securities similar to the notes. The market, if any, for the notes may not be free from similar disruptions, and any such disruptions may adversely affect the prices at which you may sell your notes if at all. In addition, subsequent to their initial issuance, the Notes may trade at a discount from their initial offering price, depending upon prevailing interest rates, the market for similar notes, our operating performance and financial condition and other factors. The Issuer does not intend to apply for the Notes to be listed on any securities exchange or to arrange for the Notes to be quoted on any quotation system. Further, the Notes are each a new issue of securities for which there is no established trading market. An active trading market may not develop for such Notes or, if developed, may not continue. If an active public trading market for the Notes does not develop or ceases to exist, the market price and liquidity of the Notes may be adversely affected.

Credit rating agencies continually revise their ratings for companies they follow, including us. Changes in our performance, leverage or industry, or changes in the credit ratings agencies’ ratings methodologies, could lead to ratings downgrades. Any ratings downgrade could adversely affect the trading price of the Notes, or the trading market for the Notes, to the extent a trading market for the Notes exists or develops. The condition of the financial and credit markets and prevailing interest rates have fluctuated in the past and are likely to fluctuate in the future, and any fluctuation may impact the trading price of the Notes.

We estimate that the net proceeds from the sale of the Notes in this offering will be approximately $2.979 billion, after deducting underwriting discounts and commissions and estimated offering expenses payable by us.

We intend to use the net proceeds from this offering for general corporate purposes, which may include among other things, financing acquisitions of additional spectrum and refinancing existing indebtedness on an ongoing basis.

Affiliates of certain of the underwriters have made commitments to provide us with secured bridge financing in an aggregate amount of up to $5.0 billion pursuant to that certain bridge commitment letter dated as of October 30, 2020, as amended on November 13, 2020. A portion of these commitments may be reduced by an amount equal to the aggregate gross proceeds of the Notes. See “Underwriting.”

See “Description of Other Indebtedness and Certain Financing Transactions” for information on our outstanding indebtedness, including as to interest rate and maturity. Certain of the underwriters and/or their respective affiliates may be lenders under, or holders of, such indebtedness and would therefore receive any portion of the net proceeds of this offering used to repay such indebtedness. See “Underwriting.”

The table below sets forth our cash and cash equivalents and capitalization as of September 30, 2020:

You should read this table in conjunction with “Management’s Discussion and Analysis of Financial Condition and Results of Operations of T-Mobile” and related notes thereto included in Parent’s Quarterly Report on Form 10-Q filed on November 5, 2020, which is incorporated by reference in this prospectus supplement.

The following table sets forth selected consolidated financial data for the Company. The data should be read in conjunction with T-Mobile’s audited consolidated financial statements and related notes as of December 31, 2019 and 2018 and for the three years ended December 31, 2019 contained in Parent’s Annual Report on Form 10-K filed on February 6, 2020 and T-Mobile’s unaudited condensed consolidated financial statements and related notes as of and for the nine months ended September 30, 2020 and 2019 contained in Parent’s Quarterly Report on Form 10-Q filed on November 5, 2020. The consolidated balance sheet data as of December 31, 2017, 2016 and 2015 and the consolidated statement of operations data for the fiscal years ended December 31, 2016 and 2015 are derived from T-Mobile’s consolidated financial statements which are not included or incorporated by reference in this prospectus supplement. T-Mobile’s unaudited consolidated financial statements have been prepared on the same basis as T-Mobile’s audited consolidated financial statements and, in the opinion of our management, reflect all adjustments, consisting of normal, recurring adjustments, necessary for a fair presentation of the results for those periods. The results for any interim period are not necessarily indicative of the results that may be expected for a full year.

T-Mobile’s historical financial data may not be indicative of the results of operations or financial position to be expected in the future. In particular, on January 1, 2020, T-Mobile adopted ASU 2016-13, “Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments” which requires a financial asset (or a group of financial assets) measured at amortized cost basis to be presented at the net amount expected to be collected. The measurement of expected credit losses is based on relevant information about past events, including historical experience, current conditions and reasonable and supportable forecasts that affect the collectibility of the reported amount. T-Mobile adopted the new credit loss standard on January 1, 2020 by recognizing a cumulative effect of initially applying the new credit loss standard on its receivables portfolio. Additionally, on January 1, 2019, T-Mobile adopted ASU 2016-02 “Leases (Topic 842)”, which requires most lessees to report a right-of-use asset and a lease liability. T-Mobile adopted the new lease standard on January 1, 2019 by recognizing and measuring leases at the adoption date with a cumulative effect of initially applying the guidance recognized at the date of initial application. Comparative information has not been restated and continues to be reported under the standards in effect for those periods. Lastly, on January 1, 2018, T-Mobile adopted ASU 2014-09, “Revenue from Contracts with Customers (Topic 606),” which requires entities to recognize revenue through the application of a five-step model, which includes: identification of the contract; identification of the performance obligations; determination of the transaction price; allocation of the transaction price to the performance obligations; and recognition of revenue as the entity satisfies the performance obligations. T-Mobile adopted the new revenue standard on January 1, 2018, using the modified retrospective method with the cumulative effect of initially applying the guidance recognized at the date of initial application. Comparative information has not been restated and continues to be reported under the standards in effect for those periods.