20 Colones

The Banco Mercantil de Costa Rica was a private commercial bank operating under Costa Rica's free banking regime, which allowed chartered institutions to issue their own circulating currency well into the early twentieth century. The central bank monopoly on note issue didn't come until 1950, meaning notes like this one were legitimate tender issued by a competing private institution — not a government emergency measure or a scrip substitute.

American Bank Note Company produced the plates in New York, as they did for the majority of Latin American private and state bank issues of this period. The Mercantil series is considerably scarcer than contemporary issues from the Banco de Costa Rica, which had deeper reserves and longer circulation runs.