2026 fiscal calendar
Know the tax date before it becomes a penalty date.
Tax bills, payment rules, and valuation-review windows are controlled by the local jurisdiction and the governing state framework. The verified record below separates published figures from dates that require confirmation with Warren County Assessment Office.
Effective rate
2026 county, municipal, and school millage varies by taxing district; Warren County publishes 2026 millage schedules, including a county rate of 3.2612 mills in the spring schedule.
Statement mailing
2026 county/municipality tax bills were mailed in advance of March 1, 2026 collections; Warren County School District bills were mailed in advance of August 1, 2026 collections.
Payment deadline
2026 county/municipality bills: discount March 1–April 30, face May 1–June 30, penalty July 1–December 31. School bills: discount August 1–September 30, face October 1–November 30, penalty December 1–December 31; unpaid taxes are available through Tax Claim February 1, 2027.
Valuation protest
September 1, 2026 for the annual assessment appeal; a new or changed assessment may be appealed within 40 days of the notice. Warren County's completed reassessment is effective January 1, 2026.
Critical payment warning
Do not assume a grace period.
The verified county record identifies the payment timing above but does not establish a universal penalty schedule for this page. Late charges, interest, collection costs, tax-sale procedures, and lien or foreclosure timelines can depend on state law and the local collector’s process. If the deadline is close or a balance is delinquent, contact the tax collector directly and request the current payoff amount in writing.
Treat the published payment deadline as a hard operational date and retain your receipt or confirmation number.
Read the calendar in order
From assessment to collection
1. Valuation and notice
Review the assessment notice as soon as it arrives. The protest window may run from the notice date rather than from the payment due date.
2. Statement and account review
Match the tax statement to the parcel or account number and confirm exemptions, assessed value, taxing units, credits, and balance.
3. Payment confirmation
Use the official collector channel, then save the receipt, transaction reference, and date posted. A bank submission is not always the same as a county posting date.