Town played Brentford in the quarter final of Southern Section. Timlin signed a two-year contract extension with Swindon on 23 June 2011. stating that he had never considered leaving the Robins despite recurring interest from Southend United. Ahead of the 2011–12 season, Timlin praised newly manager Paolo Di Canio for his influence. Despite signing the contract extension, Timlin re-joined Southend on loan again at the end of August 2011 which resulted in a permanent switch in January 2012. Southend United On 15 September 2010, Timlin joined League Two side Southend United on a one-month loan. Timlin made his debut on 25 September 2010, scoring his first goal from a 30-yard free-kick in a 3–1 win over Hereford United. Timlin made an impressive performance for Southend United and expressed an interest to extend his loan spell. Swindon Town initially agreed but later changed their mind and recalled him back to the club. On 31 August 2011, Timlin re-joined Southend United on loan for a second spell, this time on a 4-month contract. His last match on loan to Southend was on Monday 2 January 2012 against Dagenham and Redbridge. In the evening of Thursday 5 January, three days after his loan spell came to an end, it was confirmed that he would be moving to Southend United permanently for an 'undisclosed fee' On 5 February 2013, in a match against Leyton Orient, Timlin suffered a broken leg and was out of action for 8–9 months. He then missed the second leg of that game, the JPT Area Final, and the subsequent Wembley final. It was hoped that he would be back for the start of the next season 2013–14. Despite the injury, Timlin was offered, and signed, a new 2-year contract. He made his return from injury after appearing on the bench for three matches, when he came on as a substitute in the 83rd minute, in a 2–1 loss against Chesterfield on 24 August 2013. At the end of the 2014–15 season he played for Southend in the League Two play-off final against Wycombe Wanderers. Southend won in a penalty shoot-out and were promoted to League One. On 2 July 2015 Timlin signed a new 2-year contract at Southend and then a further year extension which saw him contracted until May 2018. At the end of the 2017/2018 season, Timlin held positive talks about a contract extension at Southend United