The cost of mailing a one-ounce first-class letter jumped from 47 cents to 49 cents Sunday.
According to the U.S. Postal Service, the last increase was in January 2014. Postcards, letters mailed to other countries and heavier letters aren't affected.
The word "Forever" refers to when it can be put on an envelope not how long its cost will remain unchanged.
The USPS needs to periodically adjust the price of postage to compensate for even modest levels of inflation, as its own costs—gas for mail trucks, wages, heating and lighting its buildings—go up.
Previously, the Forever stamp cost 49 cents, but the Postal Regulatory Commission ordered the USPS to drop its prices in April, the first time in 97 years.
To read more about the postage increase, read the original article here.