Ohio CAT guide
How to file the Ohio Commercial Activity Tax
A practical walk-through of filing the Ohio CAT — what to gather, where to file, the deadlines, and the mistakes that trip people up.
Last reviewed June 2026 against Ohio Department of Taxation guidance.
What you'll need
- Your Ohio-sitused taxable gross receipts for each calendar quarter
- An Ohio Business Gateway (OBG) account
Step by step
- 1Register for the CAT on the Ohio Business Gateway if your Ohio taxable gross receipts exceed $6,000,000.
- 2Track receipts sourced to Ohio under destination-based sourcing rules each quarter.
- 3Apply the annual $6,000,000 exclusion against your earliest receipts of the year.
- 4File and pay quarterly through the Gateway — due May 10, Aug 10, Nov 10, and Feb 10.
Where to file
Ohio Commercial Activity Tax Return (quarterly)
Filed via Ohio Business Gateway
Official form / filing portalDeadlines
Quarterly (annual filing discontinued after 2023).
- Q1 (Jan–Mar)May 10
- Q2 (Apr–Jun)August 10
- Q3 (Jul–Sep)November 10
- Q4 (Oct–Dec)February 10
Common mistakes to avoid
- Annual filing was eliminated after 2023 — all remaining taxpayers file quarterly.
- There is no minimum tax; you owe 0.26% only on receipts above $6,000,000.
- The exclusion is an annual amount applied to your earliest receipts, not split evenly across quarters.
Estimate your Ohio CAT and get a pre-filled worksheet first.
Open calculatorGeneral information, not tax advice — confirm the current procedure with the Ohio Department of Taxation or a qualified CPA before filing.