For decades, 15 April has been the date every American with a shoebox full of receipts circles on the calendar. This year, for anyone still licking stamps, it is the wrong one.
The Internal Revenue Service has not moved its deadline. However, changes at the United States Postal Service (USPS) are affecting how deadlines are effectively met. A change to how postmarks are applied, which was introduced last year, means paper tax returns dropped in a mailbox after 9 April may not carry a 15 April stamp by the time they are processed. This is six days earlier than the date most taxpayers have drilled into their heads; in other words, it is the new practical cutoff.
