United States securities and exchange commission logo November 22, 2022 Daniel Jones Chief Executive Officer SeqLL, Inc. 3 Federal Street Billerica, MA 01821 Re: SeqLL, Inc. Registration Statement on Form S-3 Filed November 14, 2022 File No. 333-268319 Dear Daniel Jones: 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 Sean Healy at (202) 551-5586 with any questions. Sincerely, Division of Corporation Finance Office of Industrial Applications and Services cc: Eric M. Hellige, Esq.