Oldham Athletic Edmundson signed for
Oldham Athletic on a two-year scholarship on 14 July 2013 at the age of 15. He signed a one-year professional contract on 13 May 2015. He was first included in a senior matchday squad on 22 August 2015, remaining an unused substitute in a 1–1
League One draw against
Shrewsbury Town at
Boundary Park. Nine days later, away to the same opposition, he made his senior debut in the first round of the
Football League Trophy, playing the full 90 minutes of a 0–2 defeat at the
New Meadow. He made 3 appearances for Oldham during his first season in senior football, whilst also spending time on loan at
Northern Premier League side
Ramsbottom United. After impressing in his loan spell at AFC Fylde, Edmundson returned to Oldham Athletic in January 2018, working his way into the first-team upon his return. He scored his first goal for Oldham on the final day of the 2017–18 season, netting in a 2–2 draw with
Northampton Town. He made 17 appearances for Oldham during the season, scoring once. He scored his first goal of the season in a 3–1 away win against
Cambridge United on 17 November. During the 2018–19 season, Edmundson formed an impressive partnership with veteran defender
Peter Clarke, being named in the
EFL League Two Team of the Season, while also winning Oldham's Players' Player of the Season award. In total, he made 54 appearances in all competitions over the course of the season, scoring twice. He made his Rangers and European competition debut on 18 July, starting against
St. Joseph's of
Gibraltar, in a 6–0 Rangers victory in the second leg of the
Europa League first qualifying round. He scored his first goal for the club in a 2–1 home win against
Hibernian at
Ibrox on 5 February 2020. During his first season at Ibrox, Edmundson earned the nickname 'The Fridge' from his team-mates and the Rangers supporters. On 12 March 2020, he scored in a Europa League round of 16 first leg tie against
Bayer Leverkusen, a match in which Rangers eventually lost 1–3. Edmundson made 16 appearances in all competitions during his first season at Rangers, scoring twice. He did not feature for Rangers for the remainder of the season, making only two appearances for the club as Rangers won the
Scottish Premiership title. He made his debut for Derby on 16 February in a 2–1 away win against
Wycombe Wanderers. He scored his first goal for Derby in a 2–0 win against
Huddersfield Town on 23 February 2021. Edmundson made 10 appearances for Derby during his loan spell, helping the club to stay in the
Championship on the final day of the season, following a 3–3 draw against
Sheffield Wednesday. He made his debut for Ipswich on 11 September in a 2–5 home defeat against
Bolton Wanderers at
Portman Road. He scored his first goal for the club two games later, netting the final goal in a 6–0 home win against
Doncaster Rovers at Portman Road. Edmundson quickly established himself as a key player in the Ipswich defence. On 25 January, he
captained Ipswich for the first time in a 2–0 away win against
AFC Wimbledon, as club captain
Sam Morsy was suspended. He continued to captain the team for the following three matches before handing the armband back over to Morsy following his return from suspension. Edmundson suffered an ankle injury in a 2–0 win against
Lincoln City on 8 March, ruling him out of action for the "foreseeable" future.
Middlesbrough On 30 August 2024, Edmundson signed for Championship club
Middlesbrough for the season. Ipswich recalled Edmundson from the loan on 21 January 2025 after Middlesbrough had two bids rejected to sign him permanently, but did, in fact, join the club on a permanent transfer four days later for a undisclosed fee. ==Career statistics==