Taxpayers should no longer rely on same-day postmarks for mailed property tax payments, due to a policy change from the U.S. Postal Service (USPS).

 

Residents who pay their property taxes by mail should be aware that, effective December 24, 2025, USPS is moving the postmarking process from local post offices to regional sorting centers. This may affect how mail is postmarked. Under this change, mail may not be postmarked on the day it is received at the local post office. Instead, it may be postmarked a day or two later when it is processed at the regional facility.

 

Under Wisconsin law, to be considered timely a mailed tax payment must be postmarked on or before the due date. Because of this, I strongly encourage taxpayers who rely on mailing their payments to take extra precautions. To ensure timely payment, taxpayers should bring their mail inside the post office and request a hand-stamped postmark at the counter or consider sending their payment by certified mail to obtain proof of mailing. These are the only ways to ensure your mailed payment will be considered timely.