Printing a stamp isn’t quite like printing anything else. Stamps must be nearly impossible to counterfeit, but inexpensive to print; in recent years, more than 40 billion on average have been produced each year. They must be highly consistent in appearance; easy to detach and to stick to an envelope; simple to identify–yet visually interesting.
Over the years, many printing methods have been used to meet these goals, from classic line engraving to modern full-color techniques such as gravure and lithography, and even the high-tech process of holography.
But who does the printing? You may be surprised to learn it’s not the Postal Service. From 1847 to 1894, U.S. stamps were printed by private companies, under contract. Then the Bureau of Engraving and Printing, a part of the Treasury Department, took on the job, printing almost all U.S. stamps through the 1970s. The balance has since shifted back to private firms, who will print all U.S. postage stamps after 2005.