Forever Stamps were created by the United States Postal Service® (USPS®) in 2007. They are non-denominational First Class® postage, which means that they can be used to mail First Class letters no matter what the postal rate. For example, in 2013 it cost $0.46 to mail a normal-sized letter weighing one ounce or less to an address within the United States. In 2014, the rate increased to $0.49. Customers who purchased Forever Stamps in 2013 at the rate of $0.46 each may still use those stamps to mail their First Class letters today without adding additional postage to the envelope.
An approved licensed vendor of the USPS, Stamps.com allows you to buy and print mailing and shipping labels for all USPS mail classes using a standard ink-jet or laser printer. There is a monthly service fee of $17.99 to use the service.
Forever Stamps are ideal for mailing normal-sized, one-ounce letters within the United States. If you suspect that your letter may weigh more than one ounce, be sure to weigh it prior to affixing a Forever Stamp, as heavier letters will be returned due to lack of postage. For any domestic mail piece that weighs more than one ounce, you must include additional postage along with your Forever Stamp to ensure USPS delivery. Also, you may purchase higher denomination postage stamps for heavier postage at the Post Office™.
Avoid placing two Forever Stamps on a mail piece for heavier mail. Additional ounces are much cheaper costing only $0.21 per additional ounce rather than $0.50 for a one ounce letter. If you add two Forever Stamps to a 2 ounce letter, you would be paying for an item that should only cost $0.71.
Stamps.com gives customers the convenience of printing USPS postage stamps and shipping labels for any mail class or denomination on demand. The program allows customers to easily send domestic or international mail by printing postage directly onto labels, envelopes or regular paper using your computer and printer. And Stamps.com is automatically updated — at no cost to you — every time postal rates change.