The U.S. Postal Service has put the former president on a "forever stamp," which costs 44 cents now and can be used at any time in the future.
The late president would have turned 100 last Sunday. The stamp honoring Reagan's centennial went on sale Thursday at the Ronald Reagan Presidential Library in Simi Valley.
The stamp shows Reagan at his Santa Barbara-area ranch.
It's the third Ronald Reagan stamp. The first was released after his death in 2004. It was later reissued.