The Act Prohibiting Importation of Slaves of 1807 (2 Stat. 426, enacted March 2, 1807) is a United States federal law that prohibits the importation of slaves into the United States. It took effect on January 1, 1808, the earliest date permitted by the United States Constitution.
This legislation was promoted by President Thomas Jefferson, who called for its enactment in his 1806 State of the Union Address. He and others had promoted the idea since the 1770s. It reflected the general trend toward abolishing the international slave trade, which Virginia, followed by all the other states, had prohibited or restricted since then (South Carolina, however, had reopened its trade).