This is one of those tasks that can easily fall through the cracks, and if it does, you may miss some really important mail -- like bills, bank statements and checks from people who owe you money. So, be sure to set aside some time to do this before you move. You can pick up a change of address form at the post office, fill it out and send it via snail mail. Or you can fill out the form online. You simply inform the U.S. Postal Service of your new address and the exact date when you would like your mail to be forwarded to that address. It's easy.