How is the cost of a stamp defined?

Answer 1

The cost of a stamp depends on the type of stamp being purchased. A postage stamp's cost is set by the US Postal Service and determined by the type of mailing, such as whether it is a first-class letter, bulk mailing or postcard, and the cost is often printed on the stamp itself. Tax stamps are required for some documents or transactions, such as real estate transfers, and their cost is usually determined by state law.