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OHCommercial Activity Tax (CAT)

Ohio Commercial Activity Tax (CAT): Complete Guide

Ohio's Commercial Activity Tax is a gross-receipts tax — meaning it's owed on revenue regardless of profit. Effective 2024, Ohio raised the exclusion to $3 million in gross receipts ($6 million in 2025), eliminating CAT for most small businesses but still hitting mid-market and large companies hard.

Quick Answer

Ohio's Commercial Activity Tax (CAT) is a 0.26% gross-receipts tax on Ohio-sourced revenue. For 2024, the first $3 million of receipts is excluded; for 2025 and beyond, the exclusion rises to $6 million. Filers with $1 million+ in taxable receipts file quarterly; smaller filers file annually. Unlike an income tax, CAT is owed even in unprofitable years — making it especially painful for low-margin businesses.

Who Owes It

  • Every person or entity with Ohio-sourced gross receipts above the exclusion threshold ($3M in 2024, $6M in 2025+)
  • Includes C-corps, S-corps, LLCs, partnerships, sole proprietors, trusts, and disregarded entities
  • Out-of-state businesses with $500,000+ of Ohio-sourced receipts (bright-line economic nexus)
  • Combined and consolidated taxpayer groups — affiliated entities must file together
  • Pass-through entities owe CAT at the entity level — separate from owner-level Ohio personal income tax

Filing Details

Due date
Quarterly filers ($1M+ in receipts): 10th day of the second month after each quarter (May 10, August 10, November 10, February 10). Annual filers: May 10.
Minimum tax
No flat minimum after the 2024 reforms. Businesses below the exclusion owe $0 but may still need to file or cancel registration.
Maximum / rate
No cap — 0.26% applies to all Ohio-taxable receipts above the exclusion.
How to file
Online via Ohio Business Gateway (gateway.ohio.gov) or the Ohio Department of Taxation's CAT portal.
Payee
Ohio Department of Taxation — Commercial Activity Tax. Payment via ACH debit/credit or check.

Most Common Problems

The patterns we see most often when clients come to us with Ohio Commercial Activity Tax (CAT) problems.

1. Sourcing receipts to Ohio incorrectly

Ohio uses market-based sourcing — receipts are sourced to where the customer receives the benefit, not where the seller is located. Mis-sourcing services, software, and digital receipts is the #1 CAT audit issue and produces six- and seven-figure adjustments.

2. Failure to register after crossing economic nexus

An out-of-state business that crosses $500,000 in Ohio receipts must register within 30 days. Late registration triggers back-tax assessments going up to 7 years plus failure-to-file and failure-to-pay penalties stacked together.

3. Combined-group filing errors

Affiliated entities (50%+ common ownership) must elect combined or consolidated filing. Filing separately when combination is required produces double-counted exclusions, missed inter-company eliminations, and material assessments.

4. Successor CAT liability after asset purchase

Under R.C. § 5751.10, buyers of a business can be held liable for unpaid CAT of the seller unless they obtain a tax clearance certificate before closing. Many M&A deals miss this and the buyer inherits the seller's CAT assessment.

Attorney Playbook

How to Fix It: Step-by-Step Resolution

The same playbook our attorneys use when a new client walks in with Ohio Commercial Activity Tax (CAT) delinquency.

  1. 1

    Pull a CAT Statement of Account from Ohio DOT

    Request the full CAT account showing every assessed period, penalty, interest, and lien. Compare to your filed returns to find unfiled quarters and incorrect estimated assessments.

  2. 2

    File all missing CAT returns — zero returns included

    Failure to file is 5% per month up to 50% in Ohio (more aggressive than federal). Filing actual returns replaces estimated assessments and triggers re-computation of penalties.

  3. 3

    Request penalty abatement under R.C. § 5703.50

    Ohio grants reasonable-cause penalty waiver — file a written request with the Tax Commissioner detailing the cause. First-time-offender treatment is available for businesses with clean prior compliance.

  4. 4

    Negotiate a payment plan with the Attorney General's office

    Once a CAT assessment becomes final, collection moves to the Ohio Attorney General. Payment plans up to 36 months are routinely available; longer terms require detailed financial disclosure.

  5. 5

    Appeal to the Ohio Board of Tax Appeals within 60 days

    CAT assessments must be appealed to the Board of Tax Appeals within 60 days of the Final Determination. Missing this window forfeits all challenge rights — the assessment becomes a judgment.

Penalties & Consequences

Failure to file: 5% per month, capped at 50%. Failure to pay: 5% one-time plus interest at the federal short-term rate + 3%. Failure to register: additional $50/month, capped at $500. Officer liability for unpaid CAT exists for 'responsible parties' under R.C. § 5751.42.

Why a Tax Attorney (Not Just Your Registered Agent)

Ohio CAT cases combine gross-receipts sourcing disputes (highly technical), combined-group filing errors, successor liability, and personal-officer assessments. The 60-day Board of Tax Appeals window is jurisdictional — miss it and the assessment is final. A tax attorney coordinates the CAT, sales-tax, and employer-withholding issues that nearly always arrive together.

Frequently Asked Questions

Is CAT going away in Ohio?+

No, but it has been dramatically scaled back. The 2023 budget bill raised the exclusion to $3 million for 2024 and $6 million for 2025+. Approximately 90% of CAT filers are now below the threshold and owe $0 — but the largest 10% of businesses still pay essentially the same CAT.

Does Ohio have economic nexus for CAT?+

Yes. Ohio asserts CAT nexus over any out-of-state business with $500,000+ in Ohio-sourced gross receipts (regardless of physical presence). This bright-line rule was upheld by the Ohio Supreme Court in Crutchfield v. Testa (2016) and survives even after the Wayfair decision.

Can Ohio hold corporate officers personally liable for CAT?+

Yes. R.C. § 5751.42 imposes personal liability on officers, employees, and other 'responsible persons' who willfully fail to file, pay, or report CAT. The Ohio Attorney General routinely files personal-liability assessments alongside corporate assessments.

What's the difference between CAT and Ohio sales tax?+

CAT is paid by the business on gross receipts. Sales tax is collected from the customer and held in trust. Both can apply to the same transaction. CAT cases frequently bundle with sales-tax audits and trust-fund officer assessments — comprehensive representation is essential.

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Written by
Gregory McCauley Jr., Esq.

Tax Attorney | Civil and Criminal Tax Controversy & Litigation Specialist

Gregory McCauley Jr. is an experienced tax attorney who has personally represented more than 1,000 clients in matters ranging from civil tax controversy and IRS examinations to criminal tax defense, U.S. Tax Court litigation, and complex business disputes. His practice is built on a foundation his clients describe as rare in the tax resolution industry: genuine attention to detail, direct attorney access, and a willingness to litigate when the IRS refuses to be reasonable.

Bar Admissions
Delaware • New Jersey • United States Tax Court • United States District Court for the District of Delaware
Education
Juris Doctor, Villanova University School of Law
Last updated May 25, 2026
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Don’t Overpay Ohio. Don’t Wait for Forfeiture.

Our tax attorneys resolve Ohio Commercial Activity Tax (CAT) delinquency, federal corporate tax exposure, and officer personal liability in one coordinated strategy.

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