Last-minute tax payers who take advantage of late hours on tax night at the Lawrence post office will notice a change this year.

Although the main post office at 645 Vt. will be open from 5:30 p.m. to midnight Monday, the usual hand cancellations will not be applied to tax mailings, Lawrence Postmaster Bill Reynolds said. Increased security since the Sept. 11 terrorist attacks and the subsequent anthrax scares have prompted a need for machine cancellation, which will take place at the Kansas City processing facility.

However, as long as customers deposit their tax mailing at the main post office by midnight, they still can count on an April 15 postmark, Reynolds said.