Why Is the Dollar Symbol an “S”?

  • Dollar symbol made from paper
Dollar symbol made from paper
Credit: isak55/ iStock

The dollar sign, or “$,” is one of the most recognizable currency symbols in the world, instantly understood across languages and cultures. It also transcends currency, having become a widespread symbol in pop culture. Andy Warhol made a whole series of drawings and paintings of the dollar sign in the 1980s, while some modern artists have used the symbol in their own stylized names — think A$AP Rocky, Travi$ Scott, and Ke$ha. It’s also been used as a symbol of greed — critics of large companies might make their point by introducing the dollar sign into the name of a corporation. 

Despite the ubiquity of the dollar sign, its origins are surprisingly complex, muddied by a lack of historical record and competing theories. Far from a simple design, the dollar symbol represents a fascinating journey through economic history, global trade, and linguistic evolution.

Credit: Hoberman Publishing/ Alamy Stock Photo

Origin Theories

A number of theories exist regarding the origins of the dollar sign. Some have little supporting evidence, but are interesting nonetheless. For example, one hypothesis traces the symbol’s roots to an image of the Pillars of Hercules that appeared on the Spanish coat of arms and national currency. The image showed the two pillars wrapped in S-shaped banners, which, according to the theory, could have evolved in notation to become the dollar sign. 

Another, similar theory argues that the symbol came from the Potosí mint in Bolivia, which operated from 1573 to 1825. (The mine at Potosí was once the main source of silver for the Spanish Empire.) The mint used a stamp that featured the letters PTSI (for Potosí) imposed on top of each other, which could have created a symbol similar to the modern dollar sign. 

Yet another common theory — and most likely a popular misconception — is that the symbol stands for “United States” and originated from the abbreviation “U.S.,” with the letters superimposed and the “U” becoming stylized over time. The writer and philosopher Ayn Rand seemingly believed this theory and chose to include it in a chapter of her 1957 novel Atlas Shrugged, in which one character asks another what the dollar sign stands for. But Rand, it seems, was wrong. The United States was known as the United Colonies of North America until 1776, and evidence exists that the dollar sign was in use before the United States moniker was born — making the theory seem tenuous at best.  

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