July 10, 2025

Daniel Lochner
Chief Financial Officer
Tectonic Therapeutic, Inc.
490 Arsenal Way
Suite 210
Watertown, MA 02472

        Re: Tectonic Therapeutic, Inc.
            Registration Statement on Form S-3
            Filed July 7, 2025
            File No. 333-288539
Dear Daniel Lochner:

       This is to advise you that we have not reviewed and will not review your
registration
statement.

        Please refer to Rules 460 and 461 regarding requests for acceleration.
We remind you
that the company and its management are responsible for the accuracy and
adequacy of their
disclosures, notwithstanding any review, comments, action or absence of action
by the staff.

       Please contact Jessica Dickerson at 202-551-8013 with any questions.



                                                           Sincerely,

                                                           Division of
Corporation Finance
                                                           Office of Life
Sciences
cc:   Brandon Fenn, Esq.