How Ohio property tax works and what the homestead saves

How is your Ohio property tax calculated?

The Franklin County Auditor values each home as of January 1 and sets its taxable value at 35% of that market value. Then four steps follow, shown on the Auditor’s public tax pages:

1. Original tax: taxable value × the district’s full rate, in mills (dollars per $1,000 of taxable value).
2. Reduction: the full rate is cut by a reduction factor, which leaves the effective rate. The factor is set for each taxing district, not for each home.
3. Credits: a non-business credit and, for an owner-occupied home, an owner-occupancy credit.
4. Homestead credit, if you qualify.

The full rate adds up levies by several taxing bodies. For the City of Columbus district, the Auditor’s 2025 file lists Columbus State (0.32 mills), library and special levies (4.3), the county (20.37), the local school district (87.76) and the city (3.14), for a full rate of 115.89 mills.

Which Columbus rate applies to you?

Rates depend on the district where the parcel sits, and Columbus spans many. The Auditor’s 2025 file gives a full rate of 115.89 mills for the City of Columbus district, 127.78 for Columbus in the Hilliard school district and 147.07 for Columbus in the Worthington school district. Check your parcel’s district on your tax bill.

Who values the home, and how often?

Ohio law requires auditors to reappraise every property once every six years and to do a sales-based update in the third year (County Auditors’ Association of Ohio). The Franklin County Auditor posted tentative 2026 triennial update values on June 9, 2026. The Auditor’s preliminary figures show residential values up about 10% on average. Values are expected to be final in December 2026, and the filing deadline for a Board of Revision complaint is March 31, 2027.

A value increase does not raise your tax by the same percentage: the Auditor says rates fall when values rise, though a home that rises faster than its neighbors can still see a larger bill.

Is there a cap on increases?

I found no cap on how much one home’s taxable value or tax can rise. The Franklin County Auditor told legislators in January 2024 that Ohio law has no mechanism to protect owners who become “house rich and cash poor.” What exists instead is a rate adjustment: after a reappraisal, each levy’s rate is adjusted for the change in value of the whole taxing district, so a district does not collect a windfall. The adjustment mostly disappears when a school district is at the 20-mill floor, when a value rise passes more directly into taxes.

What does the homestead exemption save?

Ohio’s homestead exemption is means-tested. It is a credit on the bill for low-income seniors, certain permanently disabled owners and their surviving spouses (Ohio Department of Taxation).

• Income limit: $40,000 for tax year 2025 and $41,000 for tax year 2026, measured by Ohio modified adjusted gross income. No limit applies to the enhanced exemption for disabled veterans.
• Age: 65 by December 31 of the year you apply, or permanently and totally disabled as of January 1.
• Residence: you must own and occupy the home as your principal residence as of January 1.
• Deadline: for real property, apply on or before December 31 of the year for which you seek the exemption, with the county auditor (form DTE 105A for most owners).
• Moving: you must reapply at the new address.
• Denial: appeal to the Board of Revision on form DTE 106B within 60 days of the denial notice.

A 2025 law allows county commissioners to add a local-option exemption equal to the state one. It does not apply unless the commissioners authorize it, and I did not confirm whether Franklin County has.

Example: a $300,000 home in the City of Columbus district

This example uses the Auditor’s 2025 rates for district 010, which are the latest in the file. The home is owner-occupied, and the owners do not receive the homestead credit.

That is about 1.58% of the market value. I checked the same method against the Auditor’s tax page for a Columbus residential parcel with a taxable value of $27,200: original tax $3,152.20, reduction $1,798.32, non-business credit $103.50. The Department of Taxation says the rollbacks that produce these credits are 10% and 2.5%, but they do not apply to some levies approved since 2013. The 2026 update will change values and rates in December 2026.

A senior who qualifies for the 2026 homestead credit would get roughly the tax on $29,700 of value: $29,700 × 35% × 49.775 mills is about $517, before the other credits. The Auditor calculates the exact figure.

When are taxes due?

Franklin County collects a year in arrears: tax year 2025 is billed in 2026. For 2026 the Treasurer lists two due dates: a first half in late February or early March (its pages show February 28 and March 2) and a second half on July 20, 2026. Late payments cost a 5% penalty within ten days after the due date and 10% after that, plus interest under Ohio Revised Code § 323.121. The Treasurer’s page does not list 2027 dates.

To challenge your value, file a complaint with the Franklin County Board of Revision between August 25, 2026 and March 31, 2027 for tax year 2026. If you disagree with the decision, you have 30 days to appeal. Your taxes are separate from your closing costs; see closing costs in Ohio, the Columbus guide and your escrow account.