Listed as a CPA in IRS public preparer records. Source: IRS PTIN FOIA extract (Feb 2026), retrieved October 23, 2026. https://www.irs.gov/pub/foia/foia-california-extract.csv No state license number is on file. Specialties are blank until this preparer claims the listing. CPA Seek does not contact preparers.

Gregory L Hahn

CPA · Gregory L. Hahn CPA

Ontario, California 91761

Gregory L Hahn, CPA in Ontario, CA

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Gregory L Hahn, CPA in Ontario · CPA Seek