The familiar five-digit number was part of a nationwide effort to modernize the mail.

That used to be the ZIP code for Silver Cliff, Colorado, before the U.S. Postal Service removed it from use and forced the town to use neighboring Westcliffe’s ZIP code. “We lost our identity,” said ...

Mayor JohnPaul O’Connor has announced that Westlake residents will have to wait until July 2027 for the chance to secure their own unique ZIP code.

Everyone knows the ZIP code 90210—but what about these other notable codes around the country? The Zone Improvement Plan, otherwise known as the ZIP code, is the network of postal codes the U.S.