Ohio individual income tax returns are due April 15, the same day as the federal return, but every other Ohio tax runs on its own calendar. Sales tax hits on the 23rd of the month. The Commercial Activity Tax uses a May/August/November/February cycle. Property taxes are set county by county. Municipal income tax usually tracks the state April 15 date but is filed separately. Which deadlines matter to you depends on whether you’re an individual, an employer, a business owner, or a property owner, and often on more than one of those at once.1Ohio Department of Taxation. Due Dates
Individual Income Tax: April 15
Your Ohio IT 1040 is due April 15. If that date falls on a weekend or holiday, the deadline moves to the next business day. The Ohio school district income tax return (Form SD 100) shares the same April 15 due date.1Ohio Department of Taxation. Due Dates
Quarterly Estimated Payments
If you expect to owe at least $500 in Ohio income tax after withholding and credits, you generally need to make quarterly estimated payments on this schedule:
- First quarter: April 15
- Second quarter: June 15
- Third quarter: September 15
- Fourth quarter: January 15 of the following year
The same dates apply to school district estimated payments. Any due date that falls on a Saturday or Sunday pushes to the following Monday.2Ohio Department of Taxation. Estimated Payments
To avoid an underpayment penalty, your timely payments must cover at least 90% of your current-year Ohio tax liability. Paying 100% of your prior-year liability also satisfies the safe harbor, as long as you file the same return type you filed the previous year.
Sales and Use Tax: The 23rd of the Month
The Ohio Department of Taxation assigns each business a sales tax filing frequency based on the amount of tax collected. The 23rd is the anchor date across all three frequencies:1Ohio Department of Taxation. Due Dates
- Monthly filers: due by the 23rd of the month following the reporting period.
- Quarterly filers: April 23, July 23, October 23, and January 23 for the preceding quarter.
- Semi-annual filers: July 23 for the January-through-June period, and January 23 for the July-through-December period.
If the 23rd falls on a weekend or holiday, the deadline shifts to the next business day. Use tax returns, which cover taxable goods bought without paying Ohio sales tax, follow this same schedule.1Ohio Department of Taxation. Due Dates
Employer Withholding Deadlines
Ohio employers withhold state and school district income tax from wages and remit it on a schedule tied to how much they withheld during a 12-month look-back period ending June 30 of the prior year.3Ohio Department of Taxation. Employer Withholding
- Quarterly filers ($2,000 or less withheld): payment and Form IT 501 are due by the last day of the month following each calendar quarter.
- Monthly filers (more than $2,000 but under $84,000): payment and Form IT 501 are due within 15 days after the end of each month.
- Partial-weekly filers ($84,000 or more): payments must be sent by electronic funds transfer within three banking days of the end of each partial-weekly period.
Every employer, regardless of frequency, must file the IT 941 annual reconciliation and upload W-2 information electronically by January 31 of the following year. Employers who submit W-2 data through OH|TAX eServices don’t need to file a separate paper IT 3.3Ohio Department of Taxation. Employer Withholding
Commercial Activity Tax: May 10 and Quarterly
The Commercial Activity Tax applies only to businesses with more than $6 million in annual Ohio taxable gross receipts for tax years 2025 and forward. If your receipts fall at or below that threshold, you’re excluded entirely and don’t need to file.4Ohio Department of Taxation. Commercial Activity Tax (CAT)
For calendar-year filers above the threshold, the annual CAT return is due May 10, and quarterly estimated payments run on a schedule that does not match the individual estimated calendar:1Ohio Department of Taxation. Due Dates
- First quarter: May 10
- Second quarter: August 10
- Third quarter: November 10
- Fourth quarter: February 10
Businesses new to the CAT must register within 30 days of crossing the $6 million threshold.4Ohio Department of Taxation. Commercial Activity Tax (CAT)
Property Tax: Set by Your County
Ohio property taxes are paid in two installments each year, and the specific due dates vary by county. Ohio Revised Code 323.12 sets a statutory default that lets taxpayers pay the first half by the end of December and the second half by mid-June, but county treasurers set the actual billing and collection dates for their jurisdictions.5Ohio Legislative Service Commission. Ohio Revised Code Section 323.12 In practice, many counties collect the first installment in January or February and the second in June or July. Your county treasurer’s office is the only reliable source for your exact due dates, and bills typically arrive several weeks before payment is due.
Municipal Income Tax
Many Ohio cities and villages levy their own income tax, authorized under Ohio Revised Code Chapter 718.6Justia. Ohio Revised Code Title Municipal, Chapter 718 – Municipal Income Taxes The annual municipal return is generally due April 15, matching the state and federal deadlines, though some municipalities set different dates. Estimated municipal payments run on the same quarterly schedule as the state: April 15, June 15, September 15, and January 15.
Two agencies handle collection for hundreds of Ohio localities: the Regional Income Tax Agency (RITA) and the Central Collection Agency (CCA). If your city uses one of them, you’ll file through the agency rather than directly with the city. Smaller cities that administer their own taxes sometimes operate on different schedules, so confirm with your municipality.
Fiduciary and Estate Returns
Trusts and estates with Ohio-source income file Form IT 1041. For calendar-year filers, the return is due April 15. Fiscal-year filers must file on the 15th day of the fourth month after the fiscal year ends. A federal extension matches the Ohio IT 1041 extended due date, but any tax owed is still due by the original April 15 deadline.7Ohio Department of Taxation. Pass-Through Entities and Fiduciaries – Fiduciary Income Tax Return (IT 1041)
If You Need an Extension
Filing a federal extension on IRS Form 4868 automatically extends your Ohio individual and school district income tax filing deadline to October 15. No separate Ohio extension form is required.8Ohio Department of Taxation. Ohio’s Individual and School District Income Tax Filing Extension
An extension buys you time to file, not time to pay. You must still pay at least 90% of your total tax liability by April 15 to avoid an underpayment penalty. If you owe and don’t pay by the original deadline, interest and penalties start accruing immediately, even though your return isn’t due yet. For municipal taxes, a federal extension generally covers the municipal return as well, but some self-administering cities may require a separate request if you don’t have a federal extension on file.
What Late Filing and Late Payment Cost
Interest on delinquent state taxes for calendar year 2026 is 7%, running from the date the payment was due until the date it’s paid. Property tax interest runs at a lower 4% for 2026.9Ohio.gov. Department of Ohio Taxation – Determination of the Interest Rates Pursuant to Section 5703.47 of the Ohio Revised Code
The late-filing penalty for the Ohio IT 1040 is the greater of 5% of the tax due or $50 for each month the return is late, capped at 50% of the tax due or $500. The penalty applies even if the late return results in a refund. The late-payment penalty is double the annual interest rate, which works out to 14% for 2026.10Ohio Department of Taxation. Ohio Individual Income Tax Failure to File Notice
School district income tax carries its own penalties: $50 for each month the return is late, up to a $500 maximum, regardless of whether you owe tax. The late-payment penalty is double the interest amount owed.11Ohio Department of Taxation. Ohio School District Income Tax Failure to File Notice
A business that files or pays the CAT late faces a penalty equal to the greater of $50 or 10% of the tax due for that period. If an audit uncovers additional tax owed, the Tax Commissioner can add up to 15% more. Businesses that ignore a registration notice and fail to pay within 60 days can face another 35% penalty on top of that.12Ohio Legislative Service Commission. Ohio Revised Code 5751.06 – Penalty for Late Filing or Delinquent Payment County treasurers add their own fees to delinquent property tax accounts, so the real cost of a late property tax payment varies by jurisdiction.