The Wisconsin Department of Revenue (DOR), State and Local Finance Division, has announced an important change that may affect how property tax payments are processed and considered timely.
What’s Changing?
Effective December 24, 2025, the United States Postal Service (USPS) will transition its postmark process from local post offices to regional sorting centers. As a result, postmark dates may no longer reflect the actual day a payment was dropped off at a local post office.
Why This Matters for Taxpayers
This change has raised concerns about the timeliness of mailed property tax payments, particularly for payments mailed close to the due date. Delays in postmarking could cause a payment to appear late, even if it was mailed on time.
The DOR recommends that taxpayers:
- Mail property tax payments earlier than usual, or
- Consider alternative payment methods to avoid potential delays.
How Postmarks Affect Property Tax Payment Timeliness
Under Wisconsin law:
- Payments received within the five working-day grace period
These payments are considered timely regardless of the postmark date (secs. 74.11 and 74.12, Wis. Stats.). - Payments received after the grace period
These must be properly addressed and postmarked before midnight on the due date to be considered timely (sec. 74.69(1), Wis. Stats.). - Late payments
A payment may still be considered timely if the delay was caused by a USPS delay or administrative error (sec. 74.69(2), Wis. Stats.).
If a USPS Delay Occurs
If a taxpayer believes their payment was late solely due to a USPS delay or administrative error, state law provides an option for review:
- The taxpayer may submit a written request to the county treasurer asking the county board to review the payment’s timeliness (sec. 74.69(3)(b), Wis. Stats.).
- The county board will determine whether the payment can be considered timely if the delay was caused only by USPS issues or administrative error (sec. 74.69(3)(c), Wis. Stats.).
Our Recommendation: Consider Paying Online or In Person
To avoid uncertainty related to postmark delays, taxpayers may want to consider paying property taxes online or in person, especially if they want clear proof of payment by December 31, 2025. These methods provide immediate confirmation and reduce the risk of mail-related delays.
If you choose to mail your payment, we strongly encourage sending it well in advance of the due date.
