Ohio CAT in 2026: the $6 Million Exclusion, Who Still Files Quarterly, and What to Do With a CAT Account You No Longer Need
· RKube Services
Ohio CAT in 2026: the $6 million exclusion, who still files quarterly or annually, a worked example of the exclusion across the quarters, and how to close a CAT account you no longer need.
For most of its history, Ohio's Commercial Activity Tax (CAT) reached almost every business in the state. If you had more than $150,000 of Ohio gross receipts, you registered, filed and paid at least an annual minimum tax. That's no longer how it works. Since 2025, the CAT applies only to taxable gross receipts above $6 million a year, and most small businesses in Columbus, Cleveland, Cincinnati and Dayton have dropped out of it entirely.
The problem is that a lot of them don't know it, and a smaller group doesn't realize they're still in. This guide covers the 2026 numbers, who still files and when, a worked example of how the exclusion runs through the quarters, and what to check if you still have an open CAT account.
The Ohio (OH) CAT numbers for 2026
The rules come from Ohio Revised Code Chapter 5751 and the Department of Taxation's guidance on the 2023 budget changes (Information Release CAT 2023-01).
| Item | Rule for 2026 | Source |
|---|---|---|
| Exclusion amount | $6,000,000 per calendar year (it was $3,000,000 for 2024) | ORC 5751.01(R) |
| Tax rate | 2.6 mills per dollar, which is 0.26% of taxable gross receipts above the exclusion | ORC 5751.03 |
| Annual minimum tax | Eliminated starting January 1, 2024 | CAT 2023-01 |
| Annual filing | Eliminated. The 2023 annual return, due May 10, 2024, was the last one | CAT 2023-01 |
| Filing frequency | Quarterly only, for tax periods beginning on or after January 1, 2024 | CAT 2023-01 |
| Quarterly due dates | 10th day of the second month after each quarter ends: May 10, August 10, November 10 and February 10 | ORC 5751.051 |
| Registration | Within 30 days after your taxable gross receipts for a calendar year first exceed the exclusion amount | ORC 5751.04 |
| Late registration fee | $100 per month or part of a month, up to $1,000 (the commissioner can abate it) | ORC 5751.04 |
If a due date falls on a weekend or holiday, it moves to the next business day. The third-quarter 2026 return is due Tuesday, November 10, 2026, and the fourth-quarter return is due Wednesday, February 10, 2027.
What the $6 million exclusion really means
The exclusion is measured on taxable gross receipts, which means receipts sitused to Ohio, not your total revenue everywhere. A Cincinnati company that sells $8 million a year but ships half of it to Kentucky and Indiana has about $4 million of Ohio taxable gross receipts, under the exclusion.
The Department's guidance is direct about the result: a business with $6 million or less of taxable gross receipts for the year isn't required to file a CAT return. There's no minimum tax and no annual return to fall back on, so there's nothing to file at all.
Two details matter for owners near the line:
- Groups test together. If you file as part of a combined or consolidated elected taxpayer group, the group's taxable gross receipts from all members are compared to the $6 million exclusion, not each company on its own. Two related companies at $4 million each are a $8 million group.
- It's a calendar-year test. A business can be under the exclusion one year and over it the next. Growth, an acquisition or one large contract can change your status mid-year.
Who still files quarterly
If your Ohio taxable gross receipts will be over $6 million for 2026, you're a CAT taxpayer for 2026 and you file every quarter through the Ohio Business Gateway.
The exclusion isn't spread evenly across the year. Under ORC 5751.03, you apply the full $6 million exclusion on your first quarterly return of the calendar year, and any unused amount carries forward to the next quarters of that same year. It doesn't carry into the following year. So a growing business usually owes nothing for the first quarter or two and then pays on everything above the line.
If you cross $6 million for the first time this year, ORC 5751.04 gives you 30 days from the point your receipts first exceed the exclusion to register. Miss that and the late registration fee runs at $100 a month, up to $1,000, on top of the tax.
Worked example: a Columbus distributor over the line
A Columbus building-supply distributor expects $9,200,000 of Ohio taxable gross receipts in 2026. It's been registered for years and files quarterly. Here's how its 2026 CAT works out, quarter by quarter:
| Quarter | Ohio taxable gross receipts | Exclusion used | Exclusion left | Taxable amount | CAT at 0.26% | Due |
|---|---|---|---|---|---|---|
| Q1 2026 | $2,100,000 | $2,100,000 | $3,900,000 | $0 | $0 | May 10, 2026 |
| Q2 2026 | $2,400,000 | $2,400,000 | $1,500,000 | $0 | $0 | August 10, 2026 |
| Q3 2026 | $2,300,000 | $1,500,000 | $0 | $800,000 | $2,080 | November 10, 2026 |
| Q4 2026 | $2,400,000 | $0 | $0 | $2,400,000 | $6,240 | February 10, 2027 |
| Total | $9,200,000 | $6,000,000 | $3,200,000 | $8,320 |
The total is the same as a simple annual calculation: ($9,200,000 minus $6,000,000) times 0.26% is $8,320. What the table shows is the timing. The distributor files returns showing $0 due in May and August, then makes its first payment in November. If it budgets for CAT as a flat quarterly amount, it'll overpay in the spring and come up short in the fall.
Now take a Cleveland HVAC contractor with $4,800,000 of Ohio receipts in 2026. It's under the exclusion. It owes no CAT and files no CAT return for 2026. Its Ohio filings are its income tax returns, sales tax if it sells taxable goods, and the Cleveland municipal net profit return. If it grows past $6 million in 2027, it registers within 30 days of crossing the line.
Still have an open CAT account? Check it
When the exclusion rose, the Department said it would generally cancel the accounts of taxpayers at or under the threshold, with the cancellation effective December 31, 2024, after the final quarterly return for 2024 was filed by February 10, 2025.
"Generally" leaves room for accounts that stayed open. That happens with businesses that had a large year in 2024, groups whose members changed, or owners who never logged into the Gateway after the change. An open account can mean the Department expects quarterly returns, and missing returns can produce non-filer notices and estimated assessments, even when no tax is actually owed.
What to do:
- Log into the Ohio Business Gateway and look at your CAT account status and filing history.
- If you're under $6 million for 2026 and the account is still active, request cancellation through the Department's business account update process, and keep the confirmation with your records.
- If you received a notice for a quarter you didn't file, respond to it with your gross receipts for the period. A missing return isn't the same as tax owed, but the notice has to be answered.
- If you expect to be over the exclusion next year, keep the account and calendar the four quarterly dates instead.
A quick Ohio (OH) CAT checklist for 2026
- Total your Ohio-sitused gross receipts for 2026 so far, and project the full year. Use the group total if you're in a combined or consolidated group.
- Under $6 million: no CAT return. Confirm your Gateway account is cancelled or inactive.
- Over $6 million: file every quarter, apply the full exclusion on the first return of the year and carry the rest forward.
- First time over: register within 30 days of crossing the line.
- Put November 10, 2026 and February 10, 2027 on the calendar if you're a 2026 taxpayer.
- Track Ohio-sitused receipts separately in your books by quarter, so the CAT returns tie to the same sales numbers as your income tax return.
Common questions about the Ohio (OH) CAT
My Dayton LLC made $1.2 million last year. Do I file anything for CAT? No. You're far under the $6 million exclusion, there's no minimum tax anymore, and there's no annual return. Your CAT obligation for 2026 is nothing.
Is the $6 million based on total sales or Ohio sales? Ohio taxable gross receipts, meaning receipts sitused to Ohio under the CAT rules. Sales delivered outside Ohio generally don't count toward the exclusion.
We crossed $6 million in September. Did we owe tax for the whole year? You owe 0.26% on Ohio taxable gross receipts above $6 million for the calendar year. Register within 30 days of crossing the line, and file the quarterly returns the Department requires from that point.
Does the unused exclusion carry into next year? No. It carries forward only to later quarters within the same calendar year. Each January the full $6 million starts over.
Is the CAT the same as the Ohio municipal income tax? No. The CAT is a state tax on gross receipts. Municipal income tax is a city tax on net profits and wages, filed with your city, RITA or CCA, and it applies to small businesses whatever their CAT status.
What's the penalty for not registering on time? $100 for each month or part of a month the registration is late, up to $1,000, plus any tax, penalty and interest on the returns themselves. The commissioner can abate the registration fee.
This guide is general information based on the Ohio Revised Code and the Department of Taxation's published guidance as of October 2026. CAT sourcing rules have their own details, so check how your specific receipts are sitused before relying on the exclusion.
Know which side of the line you're on
RKube Services handles bookkeeping and tax prep for small businesses across the US and Canada, including companies in Columbus, Cleveland, Cincinnati and Toledo. We keep your books current, so you know well before November whether your Ohio receipts are heading past $6 million, and we track the CAT quarters, sales tax and municipal returns alongside your federal deadlines. Start with a free scoping call and a 30-day trial: call (984) 234-7030 or visit rkubeservices.com.