Initial Statement of Beneficial Ownership (3)

FORM 3	UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES	OMB APPROVAL OMB Number: 3235-0104 Estimated average burden hours per response... 0.5
	Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

1. Name and Address of Reporting Person ^*

Gasser Elizabeth Anne

2. Date of Event Requiring Statement (MM/DD/YYYY) 6/2/2021

3. Issuer Name and Ticker or Trading Symbol

TANDEM DIABETES CARE INC [TNDM]

(Last) (First) (Middle)

C/O TANDEM DIABETES CARE, INC., 11075 ROSELLE STREET

4. Relationship of Reporting Person(s) to Issuer (Check all applicable)

_____ Director _____ 10% Owner
___X___ Officer (give title below) _____ Other (specify below)
EVP, Chief Strategy Officer /

(Street)

SAN DIEGO, CA 92121

(City) (State) (Zip)

5. If Amendment, Date Original Filed(MM/DD/YYYY)

6. Individual or Joint/Group Filing(Check Applicable Line)

_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Common Stock	975	D

*Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)*
1. Title of Derivate Security (Instr. 4)	2. Date Exercisable and Expiration Date (MM/DD/YYYY)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
1. Title of Derivate Security (Instr. 4)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	4. Conversion or Exercise Price of Derivative Security		6. Nature of Indirect Beneficial Ownership (Instr. 5)
Stock Option ⁽¹⁾	⁽²⁾	⁽³⁾	Common Stock	38247.0	$89.54	D
Stock Option ⁽¹⁾	⁽⁴⁾	⁽³⁾	Common Stock	13761.0	$82.34	D
Restricted Stock Unit ⁽¹⁾	⁽⁵⁾	⁽⁵⁾	Common Stock	5962.0	$0.0	D
Stock Option ⁽¹⁾	⁽⁶⁾	⁽³⁾	Common Stock	7940.0	$81.63	D
Restricted Stock Unit ⁽¹⁾	⁽⁷⁾	⁽⁷⁾	Common Stock	2599.0	$0.0	D
Performance Stock Unit ⁽¹⁾	⁽⁸⁾	⁽⁸⁾	Common Stock	2599.0	$0.0	D

Explanation of Responses:
(1)	Granted pursuant to the Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan, as amended, and the agreements related thereto (the "2013 Plan").
(2)	The date of grant of the option was 02/18/2020. 25% of the shares subject to the option vested on 02/18/2021 and the remainder vests in 36 equal monthly installments thereafter.
(3)	The expiration date for these options is 10 years from the date of grant.
(4)	The date of grant of the option was 05/27/2020. 25% of the shares subject to the option vested on 05/27/2021 and the remainder vests in 36 equal monthly installments thereafter.
(5)	The date of Restricted Stock Unit ("RSU") grant was 05/27/2020. RSU vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on the one year anniversary of the grant date, and the remaining shares shall vest in twelve (12) equal quarterly installments thereafter, subject to the terms of the 2013 Plan. Each RSU represents a contingent right to receive either one share of common stock of the Issuer or cash in lieu thereof, at the Issuer's discretion, in accordance with the terms of the 2013 Plan.
(6)	The date of grant of the option was 05/18/2021. 25% of the shares subject to the option will vest on 05/18/2022 and the remainder vests in 36 equal monthly installments thereafter.
(7)	The date of Restricted Stock Unit ("RSU") grant was 05/18/2021. RSU vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on 05/15/2022, and the remaining shares shall vest in twelve (12) equal quarterly installments thereafter, subject to the terms of the 2013 Plan. Each RSU represents a contingent right to receive either one share of common stock of the Issuer or cash in lieu thereof, at the Issuer's discretion, in accordance with the terms of the 2013 Plan.
(8)	Each performance stock unit ("PSU") represents a contingent right to receive one share of Tandem Diabetes Care, Inc. (the "Company") common stock based upon the achievement of certain pre-defined performance metrics as of December 31, 2024 (the "Measurement Date"). The number of shares issued may range from 0% to 200 % of the amount specified above, based upon (i) Company's actual performance relative to the pre-defined performance metrics, and (ii) subject to the awardee's continuing service through the Measurement Date. If minimum performance metrics are not met, no PSU's will vest.

Reporting Owners
Reporting Owner Name / Address	Relationships
Reporting Owner Name / Address	Director	10% Owner	Officer	Other
Gasser Elizabeth Anne C/O TANDEM DIABETES CARE, INC. 11075 ROSELLE STREET SAN DIEGO, CA 92121			EVP, Chief Strategy Officer