[WayneS]

I thought they started issuing stamps without denominations on them about 5 years ago.

[TomGuy]

They were.

The stamps did not have a printed denomination/designation, just the words “first class” on them.

I still have a few from prior to the last increase.

[Yo-Yo]

I thought they started issuing stamps without denominations on them about 5 years ago.

From the fine article:

"The Forever Stamp, first issued in April 2007 and featuring the Liberty Bell, was designed for use regardless of changes in postal rates. They are sold at the prevailing price of domestic first-class postage.

The Postal Service says that 28 billion Forever Stamps have been sold since, generating $12.1 billion in total revenue. The stamps without denominations already account for 85 percent of its stamp program, the service says. "

This article is about the first commemorative stamps without a denomination.