The 2013–14 season was Colchester United's 72nd season in their history and sixth successive season in the third tier of English football, League One. Alongside competing in the League One, the club also participated in the FA Cup, the League Cup and the Football League Trophy.

In Joe Dunne's first full season in charge of the club, he brought in some of his loanees from the 2012–13 season on permanent contracts, including Craig Eastmond, Sanchez Watt and Sam Walker. There was an emphasis on youth as the U's brought through a number of their Academy products and handed them their first-team debuts throughout the season. Dunne effectively secured League One football for another season in the penultimate game when they soundly beat already-promoted Brentford 4–1 before securing victory on the final day of the season at Walsall.

2013–14 Colchester United F.C. season

Colchester had a second successive season of exiting the cup competitions at the earliest possible stage following heavy defeats by Peterborough United and Dagenham & Redbridge in the League Cup and Football League Trophy respectively, while they pushed Sheffield United close in the FA Cup first round after coming back from 2–0 down at half-time to level the score before a late Sheffield penalty decided the tie.

2013–14 Colchester United F.C. season

Season overview

Pre-season

Having narrowly avoided relegation to League Two on the final day of the previous season, manager Joe Dunne began strengthening the team early in pre-season, announcing former Arsenal loanee Craig Eastmond had signed a pre-contract agreement with the club on 20 May. Dunne had already allowed Matt Heath and Jackson Ramm to search for a new club with their contracts expiring in June.

2013–14 Colchester United F.C. season

Colchester's development squad was bolstered first by the signing of Milton Keynes Dons youth-team product Mason Spence, and the news that young striker Freddie Ladapo had signed a new one-year contract to remain with the club. Goalkeeper Mark Cousins also extended his stay at the club, agreeing a new one-year contract on 14 June.

Long-serving defender John White decided to bring an end to his nine-year stay with Colchester after rejecting a reduced-terms contract offer by the club. However, last seasons joint-leading goalscorer Jabo Ibehre agreed a two-year contract extension on 17 June.

On 28 June, another former Arsenal loanee joined the club on a permanent basis when Sanchez Watt signed a two-year contract with the club. Another development squad signing was made on 2 July when former Queens Park Rangers midfielder Conor Hubble signed following a trial period at the club.

The first-team squad played their first friendly of pre-season on 10 July when they beat Heybridge Swifts 2–1. Ben Newson had given the home side a first-half lead prior to Craig Eastmond being stretchered off following a challenge from Ryan Doyle. The U's got themselves back into the game prior to the hour mark through John-Joe O'Toole following a Drey Wright assist. Wright then turned scorer with 18-minutes remaining to earn a narrow victory. On 12 July, Colchester faced AFC Sudbury and secured a 5–0 win with a brace from Sammie Szmodics and goals from triallist Phil Roberts, Marcus Bean and John-Joe O'Toole. The following day, Colchester collected another win with a 2–0 victory at Bishop's Stortford as Gavin Massey and Clinton Morrison scored.

On 16 July, Colchester signed Chelsea's Ghanaian defender Daniel Pappoe in a sixth-month loan deal, having already featured in Colchester's previous two friendly matches. They then took on West Ham United in a friendly fixture the same day. West Ham won 2–1 courtesy of goals from Joe Cole and James Collins. Jabo Ibehre scored a consolation for Colchester from a Tosin Olufemi cross with the final kick of the game.

On 19 July another Chelsea player and former loanee rejoined the club when Sam Walker signed until 19 January. He then featured in Colchester's 0–0 draw with Tottenham Hotspur at the Colchester Community Stadium that evening. The following day, the U's faced Braintree Town at Cressing Road where they won 4–1 with goals from Andy Bond, Marcus Bean, Freddie Ladapo and Ryan Melaugh. Sean Marks pulled a goal back for the home side at 3–1.

Colchester faced local rivals Ipswich Town in their next friendly on 23 July but were beaten 3–0 by the visitors. Ex-U's player Anthony Wordsworth set up Luke Chambers for the first goal, with later goals added by David McGoldrick and Daryl Murphy.

John-Joe O'Toole made a move to Bristol Rovers for an undisclosed fee on 24 July having previously spent time on loan there during the 2012–13 season. Also on 24 July, Colchester travelled to play Histon where they won 1–0 thanks to a David Wright goal.