Like Sancho, Rashford has left Manchester United on a temporary deal, though his future remains uncertain.
Sancho, who joined Chelsea on loan last summer, is going to make the move permanent at the end of the season as part of a buy obligation.
Rashford had posted on social media about his move to Villa on loan, thanking United for letting him get regular game time.
"He's back," was Sancho’s simple response to his fellow former England international.
"I would like to thank Manchester United and Aston Villa for making this loan deal happen," Rashford had written.
"I was lucky to have a few clubs approach me but Aston Villa was an easy decision - I really admire the way that Aston Villa have been playing this season, and the managers’ ambitions.
"I just want to play football and am excited to get started. I wish everyone at Manchester United all the best for the rest of the season."