The United States agreed to pay France $15 million for the Louisiana Purchase.
The price covered roughly 828,000 square miles of territory, making the transaction one of the largest land deals in United States history. American negotiators Robert Livingston and James Monroe had initially been authorized to pursue New Orleans and nearby areas, but France unexpectedly offered the entire Louisiana Territory. They accepted the offer after deciding that the opportunity might disappear if they waited for detailed instructions from President Thomas Jefferson.
The treaty was signed on April 30, 1803. The payment was structured through cash and U.S. government bonds, with the United States also assuming certain claims by American citizens against France. The territory’s exact boundaries were not perfectly settled at the moment of purchase.
The acquisition nearly doubled the size of the United States and opened the way for later exploration, territorial organization, and state formation. Its cost is often remembered as a simple lump sum, but the financial arrangement and later boundary negotiations added important complexity.