Pinckney's Treaty, also known as the Treaty of San Lorenzo or the Treaty of Madrid, was signed on October 27, 1795 by the United States and Spain.

It defined the border between the United States and Spanish Florida, and guaranteed the United States navigation rights on the Mississippi River. With this agreement, the first phase of the ongoing border dispute between the two nations in this region, commonly called the West Florida Controversy, came to a close.Thomas Pinckney negotiated the treaty for the United States and Don Manuel de Godoy represented Spain. It was presented to the United States Senate on February 26, 1796, and, after debate, was ratified on March 7, 1796. It was ratified by Spain on April 25, 1796 and ratifications were exchanged on that date. The treaty was proclaimed on August 3, 1796.