The price of postage stamps was expected to increase by a penny Monday, including the Forever Stamp.
The boost to 42 cents was part of what was expected to be an annual price adjustment by the Postal Service.
A new law regulating the Post Office made it easier to raise rates, as long as the agency did exceed the rate of inflation.
Rates were expected to be adjusted each May.
The special Forever Stamps, which feature an image of the Liberty Bell, remain valid, regardless of any postal rate increase. Buy Forever Stamps online.
Post Office officials said they have printed an additional 1.5 billion, 1 cent stamps in anticipation of the demand from people who still had regular, 41 cent stamps.
The penny stamps feature a special Tiffany Lamp design. Buy 1 cent stamps online.
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