Filed Pursuant to Rule 424(b)(3)
Registration No. 333-223336
PROSPECTUS SUPPLEMENT No. 1 dated November 2,
2020
To Prospectus Supplement dated August 3, 2018
(To Prospectus dated March 1, 2018)

IMPORTANT NOTICE REGARDING
PNM RESOURCES, INC.
DIRECT PLAN
(a stock purchase and dividend reinvestment
plan)
Dear Valued Investor:
As previously announced, on October 20, 2020, PNM Resources,
Inc., a New Mexico corporation (“PNM Resources”), Avangrid, Inc., a
New York corporation (“AVANGRID”), and NM Green Holdings, Inc., a
New Mexico corporation and wholly-owned subsidiary of AVANGRID
(“Merger Sub”), entered into an Agreement and Plan of Merger (the
“Merger Agreement”) pursuant to which Merger Sub will merge with
and into PNM Resources (the “Merger”), with PNM Resources surviving
the Merger as a direct wholly-owned subsidiary of AVANGRID.
Pursuant to the Merger Agreement, each issued and outstanding share
of the common stock of PNM Resources (“PNM Resources common stock”)
(other than certain shares held by parties to the Merger Agreement
or their wholly-owned subsidiaries or certain Dissenting Shares (as
defined in the Merger Agreement)) will, at the effective time of
the Merger, be converted into the right to receive $50.30 in cash
(the “Merger Consideration”). Following the Merger, PNM Resources
common stock will be delisted from the New York Stock Exchange and
deregistered under the Securities Exchange Act of 1934, and PNM
Resources will no longer be required to file periodic reports with
the Securities and Exchange Commission in respect of PNM Resources
common stock. Completion of the Merger is subject to the
satisfaction or waiver of certain customary closing conditions and
approvals.
As required by the Merger Agreement, PNM Resources has
amended the PNM Resources, Inc. Direct Plan (the “Plan” or “PNM
Resources Direct”) to terminate the right to purchase shares under
the Plan with respect to any cash dividends and first-time or
optional cash investments that are not received by noon Eastern
Time on November 17, 2020. No purchases of shares of
PNM Resources common stock under the Plan will occur after
November 18, 2020.
This prospectus supplement (“Supplement”) is dated November 2,
2020 and updates the Prospectus Supplement dated August 3,
2018 to the Prospectus dated March 1, 2018. This Supplement
updates certain information in the Prospectus Supplement dated
August 3, 2018 to reflect the termination of the right to
purchase shares of PNM Resources common stock under the Plan
effective November 17, 2020.