United States securities and exchange commission logo May 18, 2020 Mark Partin Chief Financial Officer Blackline, Inc. 21300 Victory Boulevard, 12th Floor Woodland Hills, CA 91367 Re: Blackline, Inc. Form 10-K for the Year Ended December 31, 2019 Filed February 27, 2020 File No. 001-37924 Dear Mr. Partin: We have completed our review of your filing. 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. Sincerely, Division of Corporation Finance Office of Technology