The 22-year-old right back will spend the next month with Leeds, which is sixth in the League Championship.
Leeds manager Simon Grayson says on Wednesday "we're delighted Aston Villa have agreed to let him come here. He's a player that they have high hopes for."
Lichaj, who made his U.S. national team debut last fall, has played eight matches for Villa in all competitions this season. He last appeared in a 4-0 loss to Manchester City on Dec. 28, and the Villans have obtained right back Kyle Walker on loan from Tottenham.