November 20, 2019 Jeffrey W. Dunn President, Chief Executive Officer and Chairman SI-BONE, Inc. 471 El Camino Real, Suite 101 Santa Clara, CA 95050 Re: SI-BONE, Inc. Registration Statement on Form S-3 Filed November 13, 2019 File No. 333-234679 Dear Mr. Dunn: 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 Jeffrey Gabor at 202-551-2544 with any questions. Sincerely, Division of Corporation Finance Office of Life Sciences cc: Brett White, Esq.