Mailboxes are common sights around the world, but the colors in which they are painted vary from country to country. In France, they are yellow, and in Ireland, they are green, while red is used in both Italy and the UK. 

However, in the United States, mail collection boxes are commonly painted blue. As the United States Postal Service (USPS) notes on its website: “USPS collection boxes are typically blue, freestanding units, located at post offices and other strategic locations.” 

So what is the story behind this use of color for the country’s mail depositories? It’s actually a much more recent choice than you might think. Here is a look at the reasons why mailboxes in the U.S. are blue.

The Origins of Mailboxes in the United States

Early mail collection boxes in the United States were not actually blue at all, but went through a range of other colors before reaching the one which is used today. The earliest known color used on official United States mailboxes was green, as referenced in The New York Times in 1860, followed by red mailboxes in the 1880s to early 1890s. 

The use of red for U.S. mailboxes was ultimately abandoned because the boxes were sometimes confused for police call boxes, which were painted the same color. Mailboxes then began to be painted a silver-white color in 1897, before returning to green in 1905, which became the standard color over the next few decades.

Blue Enters the Chat

The move towards blue began in 1955 when the Postmaster General at the time, Arthur Summerfield, announced that mailboxes would be painted red, white, and blue, the colors of the American flag, so that people could recognize them with ease and not confuse them with any other kind of depository. 

The colors were structured across the box by painting the upper half red, the lower half blue, and the notice on the front of the box white. However, by 1964, efforts were underway to simplify the process of painting the boxes by switching to a single color instead of three. 

The idea of using blue alone was suggested by the design firm Loewy/Snaith. While their initial proposal of using a sky blue shade was ultimately rejected, tests done on mailboxes in a handful of cities using a darker shade of blue garnered favorable responses. By 1969, the Post Office Department decided that this dark blue would be the standard color for all mailboxes.

The following year, moves toward the gradual rollout of dark blue mailboxes were made, and by 1971, this shade became the standardized color for mailboxes across the entirety of the United States. The association of mailboxes in the U.S. with the color blue continues to this day.

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