The United States trade dollar was a dollar coin minted by the United States Mint to compete with other large silver trade coins that were already popular in East Asia. The idea first came about in the 1860s, when the price of silver began to decline due to increased mining in the western United States. A bill providing in part for the issuance of the trade dollar was eventually put before Congress, where it was approved, and signed into law as the Coinage Act of 1873. The act made trade dollars legal tender up to five dollars. A number of designs were considered for the trade dollar, and an obverse and reverse created by William Barber were selected.

The dollar coin is a United States coin with a face value of one United States dollar. Dollar coins have been minted in the United States in gold, silver, and base metal versions. Dollar coins were first minted in the United States in 1794.