The 26-year-old winger moves to Northampton after the expiry of his contract at AFC Wimbledon.
Potter is well known to manager Chris Wilder with the two having worked together at Oxford United and the lure of working under his former boss was a 'no brainer' according to the player.
He told BBC Radio Northampton: "I've had an up and down 18 months after a bad injury and want to kick on now."
"I went to Wimbledon to get a run of games, now it's my challenge to get back to the level I was at before under Chris."