Can you guess how much are stamps now to mail a letter? The closest answer will be the winner, but be careful. Do not go too far. You'll have to leave the game. The Postal Service has a long and interesting history. Did you know that the first post office in America was established in 1639? The Pony Express, a mail service that used horseback riders, operated from 1860 to 1861. In 1845, the first postage stamp, called the Penny Black, was issued in Great Britain. The US Postal Service is the second largest civilian employer in the United States, behind Walmart. Mail carriers have been known to deliver mail by boat, dog sled, and even on snowshoes. And the answer is... 63 cents. Letters. Standard-sized, rectangular envelope stamps. Start at 63 cents.