The Unlikely Origins of the Dollar Sign

Two vertical lines crossed by a graceful S — the dollar sign feels as native to American currency as the green ink on the bills. But the symbol didn’t spring from independence or revolution; it probably evolved from a tangle of handwriting, international trade, and a touch of laziness.

In the late 1700s, Spanish pesos — known as "pieces of eight" — were the most common currency in the American colonies, long before the United States minted its own money. These were abbreviated as “Ps” or “P^s” for “pesos,” but traders often combined the P and the S in quick script, swooping them together for speed. Over time, the top curve of the P got squashed into forgetfulness, leaving just an overlaid S and vertical slash. It was practical shorthand, not the work of revolutionaries or designers.

There's a competing story — one you’ll still see in textbooks — that claims the dollar sign comes from superimposing the letters “U” and “S” for "United States." The problem: printed examples of the dollar symbol appear in business ledgers years before the U.S. was formally established. The Peso shorthand story simply fits the timeline better and matches handwriting samples from colonial clerks. (If you dig into 18th-century ledgers, you’ll find dollar signs next to 8s and references to pesos, not American dollars.)

Originally, the symbol almost always used two vertical lines, a nod to the pillars of Hercules (which appeared on the Spanish “pillar dollar”). As American printers took up the sign, one line got dropped for clarity—or maybe just to save time and ink. Today, one-bar and two-bar dollar signs both persist, but the one-bar version rules on keyboards and cash registers everywhere.

Even the most familiar symbols hide convoluted stories in their swoops and dashes. The dollar sign, born of expedience and cultural exchange, is a reminder that what we see every day often has a tangled past under the surface.