The silver real (Spanish: real de plata) was the currency of the Spanish colonies in America. Gold escudos (worth 16 reales) were also issued. The coins circulated throughout Spain's colonies and beyond, with the eight-real piece, known in English as the Spanish dollar, becoming an international standard and leading to, among other currencies, the United States dollar. Spanish dollars and their fractions remained legal tender in the U.S. until 1857.

From 1572 to 1773 Spanish colonial silver coins were cobs. Initially cut from a silver bar and hammer struck on a coin die, they were accurate in weight, however unlike machined coins, they were often irregular in shape, especially if a coin was clipped by the mint to reach the proper weight. Later similar, but better shaped cobs were produced on screw presses. Around 1730, cobs slowly began to be phased out and replaced with milled reales. The mechanical press made coin manufacturing much easier and more standardized.

During the Age of Exploration, much of Spain’s wealth was lost in shipwrecks. Many colonial coins have been recovered from shipwrecks, excavations, and even on American soil, where Spanish coinage was valid currency.