As of this day in 1845, Americans have paid the same amount to mail letters regardless of where they are.

The Postal Act was the beginning of a standardized postal service in the United States. It mandated a cost of five cents postage for a regular letter not traveling more than three hundred miles. The price went up from there at a predictable scale, depending on what you were sending and how far it was going, creating the postal standards we recognize today. Before that, prices for mail sent through the U.S. postal service were extremely complicated to calculate, which meant that most people just gave up and paid a private mail carrier. The private carriers' rates undercut the fledgling United States Postal Department, too.

The Postal Act changed this by lowering postage rates and simplifying the process of figuring out how much it would cost to ship a piece of mail. It also made it feasible to have stamps be the only way to pay for mail.

The Postal Act didn't standardize everything all at once. For example, the first federally issued postage stamps didn’t become available until July 1847, writes the National Postal Museum’s Kristin Clark.

“Prior to this date, postage stamps were in existence; however, they were not endorsed by the federal government,” she writes. Only eleven local post offices issued "provisional" government-endorsed stamps. They were called that because they filled the gap between postal standardization and the introduction of the first federal stamp.

Ranging from James Buchanan’s signature on a ten-cent stamp from Baltimore to the easily-recognizable face of George Washington on the New York five cent stamp, these provisionals were issued by eleven post offices and vary wildly in sophistication and imagery.

“The provisionals were valid only at the issuing post office, and they were as novel and convenient to the public in 1845 as plastic debit cards are to us today,” wrote the Siegel Auction Galleries in the introduction to their collection of provisionals.

Although it took the U.S. postal service to make stamps official, it took stamps to make the service viable, Clark writes. Before the issue of a federal stamp, it was perfectly fine to pay cash in order to mail a letter or to mail it and expect that the recipient would pay for it. This led to a lot of unpaid-for mail, she writes.

“Since mail was not delivered directly to people’s homes as it is today, it was up to each indivbidual to go to the post office and find out if he had mail,” she writes. “Many people did not claim their mail and the postage was never paid.”

This problem wasn’t finally resolved until January 1856, she writes, when a stamp became a requirement to send domestic mail.