OK · 2026 appeal calendar

Oklahoma Property Tax Appeal Deadlines 2026.

Oklahoma property tax appeal deadlines and filing windows for commercial real estate. Verify with your local assessor or appeal board for the specific jurisdiction before filing.

Updated May 2026

Verify before filing. Statutory deadlines change, and many counties operate on their own schedule inside the state framework. Always confirm the current year's window with the assessor or appeal board for the specific jurisdiction before relying on a date.

2026 appeal calendar

Oklahoma deadlines at a glance.

State-level deadlines plus major sub-jurisdictions where the schedule diverges from the state default. Where a column says "Varies," confirm the date with the local assessor.

Month Type Event Date Details
January RP
Assessment Date
1-Jan
January BPP
Assessment Date
1-Jan
March BPP
Tax Returns Due
15-Mar
April RP
Value Notices
Feb-Apr Issued by April starting in February
April BPP
Appeal Deadline
Apr-Jun Sometime from April to June, 20 days after the notices are issued. Rolling issuance of notices.
May RP
Appeal Deadline
1-May May 1st or 20 days after notices are mailed. Rolling issuance of notices.
November BPP
Tax Bills Issued
1-Nov
November RP
Tax Bills Issued
Nov-Dec
December RP
Tax Bills Due
31-Dec December 31st for 1st half installment, March 31st of following year for 2nd half of installment
December BPP
Tax Bills Due
31-Dec December 31st for 1st half installment, March 31st of following year for 2nd half of installment

RP = Real Property · BPP = Business Personal Property · Both = Applies to both

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