The 23-year-old left-sided player who joined Watford for £100,000 from the Imps just over a year ago will be one of seven new players unveiled at Sincil Bank.
He will replace Kevin Sandwith who has joined Macclesfield Town on a free transfer.
Swindon manager Andy King revealed: "Incredibly to me, he agreed to sign for Lincoln instead. Sometimes it is not a football choice."