 On 3 May 2012, Gilmartin was one of four players to be released by Watford after their contracts expired.Gilmartin signed a two-year contract with League Two side Plymouth Argyle in July 2012, and made 16 appearances in all competitions.He was transfer-listed by manager John Sheridan at the end of the 2012–13 season, and left the club by mutual consent in June 2013.