 As of today, you'll pay more for postage stamps. The price of a first-class Forever stamp increasing from 68 cents to 73 cents. The price of a domestic postcard from 53 cents to 56 cents. And international postcards from $1.55 to $1.65. This is the second time this year postage prices have gone up. In January, the price of a Forever stamp increased by 2 cents.