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.

Thomas Katsuyuki Koiso

CPA · Koiso & Co.

Los Angeles, California 90017

Thomas Katsuyuki Koiso, CPA in Los Angeles, CA

Specialties

No specialties are listed yet. They stay blank until the licensee claims this profile and adds them.

Licenses

No state license number is on file.

Is this you?

Claiming attaches this listing to your account so you can add specialties and contact details. CPA Seek does not email the people on these listings.

Thomas Katsuyuki Koiso, CPA in Los Angeles · CPA Seek