What did the Aztecs commonly use as currency before the Spanish arrival?

The Aztecs commonly used cacao beans as currency before the Spanish arrival. The beans were valuable because cacao was desirable, portable, countable, and difficult to grow around the highland capital of Tenochtitlan.

Cacao also had cultural importance beyond money. It was prepared as a bitter, often foamy drink called cacahuatl and was connected with ritual, tribute, merchants, warriors, and elite life. Cacao-growing regions supplied the Aztec state through trade and tribute, making the beans part of a wider economic network rather than a coinage system issued by a central mint.

Prices varied, but Spanish observers recorded beans being exchanged for food and other goods. Sources also describe counterfeit beans: people sometimes emptied cacao shells and filled them with mud or other material. Cacao was not the only medium of exchange in Mesoamerica—goods, labor, and standardized items such as copper axe money also mattered—but it was a widely recognized everyday currency.