History of United States postage rates

Initial United States postage rates were set by Congress as part of the Postal Service Act signed into law by President George Washington on February 20, 1792. The postal rate varied according to "distance zone", the distance a letter was to be carried from the post office where it entered the mail to its final destination. Rates were adopted in 1847 for mail to or from the Pacific Coast and in 1848 for mail sent from one place in the west to another place in the west. There were double and triple rates as a letter’s size increased. There were ship fees which were also added (i.e. mail to Hawaii). The ship fee, including the ship rate on letters for delivery at the port of entry, were on a per letter basis, rather than weight. The United States issued its first postage stamps in 1847. Before that time, the rates, dates and origin of the letter were written by hand or sometimes in combination with a handstamp device.

Since enactment of the Postal Reorganization Act of 1970, postage rates have been set by the Postal Regulatory Commission.

Taking the above data and plotting it yields the graph shown to the right. The dark plot is the nominal issued price of the stamp and the light plot is the price adjusted for inflation and is shown in 2016 US cents.

This plot shows that, despite the rise in the nominal cost of a first-class stamp, the adjusted cost of the stamp has stayed relatively stable. The large jumps in the early 1900s are because a change by a single penny was large compared to the cost of the stamp. For example, the price increase from $0.02 to $0.03 on July 6, 1932 was a 50% increase in cost. Additionally, while the cost of the stamp itself remained fixed, the adjusted price in 2016 dollars was not fixed over time which added to larger jumps in adjusted prices.

Domestic parcel post service was adopted in 1913, 25 years after the Post Office had agreed to deliver international parcel post packages pursuant to the Universal Postal Union treaty and various bilateral agreements with other nations. Initially, there were no or few postal regulations governing packages mailed by parcel post. E.g., to construct a bank in Vernal, Utah, in 1916, a Salt Lake City company ascertained that the cheapest way to send 40 tons of bricks to the building was by parcel post.

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