Everton Born in
Huyton, England, Walsh started his career at
Everton when he joined them at five years old. In July 2014, Walsh signed a scholarships with the academy. Eight months later, he signed his first professional contract with the club. Walsh progressed through Everton's academy, regularly appearing for the Under-18 and Under-23 sides. In November 2015, he scored a memorable goal from the halfway line during an Under-18 game against Derby. As a result, he was awarded the club's Goal of the Month for November. After his loan spell at Yeovil Town ended, Walsh continued to feature for the Under-23 sides in the 2016–17 season. He shortly signed a contract extension with the club, keeping him until 2019. Walsh then became a regular in the midfield position for the Under-23 sides, under
David Unsworth's side. His number of outstanding performance resulted in him being named Premier League 2 Player of the Month in February 2017. After helping the side win the Premier League 2 title at the end of the season, Walsh was shortlisted for the league's Player of the Year award. Walsh was also called up to the England squad for the U20 World Cup in South Korea but suffered an injury towards the end of the 2016/17 season which meant he was unable to participate.
Loan spells On 6 January 2016, Walsh joined
Football League Two side
Yeovil Town on a one-month loan, and made his debut four days later in the
FA Cup third round against
Carlisle United. He then set up a goal for
Jack Compton, who later scored a hat–trick, in a 3–2 win over
AFC Wimbledon on 30 January 2016, followed up by scoring his first goal for the club, in a 1–1 draw against
Luton Town. The initial loan was extended on two occasions, before extending it until the end of the season. Despite missing out on two occasions, due to illness and suspension, Walsh finished the 2016–17 season, making 17 appearances in all competitions. Walsh signed for
Championship club
Birmingham City on 31 August 2017, on loan until 3 January 2018. He was one of six debutants in the starting eleven for Birmingham's next fixture, away to
Norwich City; he played 57 minutes and was yellow-carded in the first half as his team lost 1–0. He appeared twice more under
Harry Redknapp's management, but not at all under successor
Steve Cotterill, and returned to train with his parent club in mid-November, although the loan remained in force until its official expiry date.
Bristol City On 5 January 2018, Walsh signed a two-and-a-half-year contract with Championship club
Bristol City, joining for an undisclosed fee. Upon joining the club, Manager
Lee Johnson said about Walsh: "I think Liam gives us something slightly different to what we have already and adds to the qualities we already have in midfield. He loves getting on the ball and is a very good passer with both his left and right foot. He's a brilliant player, who can come in and compete immediately. Hopefully he can improve and he improves us." Walsh, himself, felt leaving Everton for Bristol City was a right time for him to leave. Walsh made his Bristol City debut, coming on as a second–half substitute in the 72nd minutes, in a 2–1 loss against
Manchester City in the Semi-final first leg of the
EFL Cup. On 13 January 2018, he made his league debut for the club, where he started and played 69 minutes before being substituted, in a 1–0 loss against
Norwich City. However, Walsh spent the rest of the season being featured in and out of the first team. At the end of the 2017–18 season, he went on to make eight appearances for the side in all competitions. He scored his first goal for City in an EFL Cup tie against
Queens Park Rangers on 13 August 2019. On 2 September 2019, Walsh signed for
League One side
Coventry City on loan until the end of the season. His performances for Coventry during the 2019–20 season led to Walsh being named in the League One
PFA Team of the Year. On 14 May 2021, Walsh was released by Bristol City following the expiration of his contract.
Swansea City Walsh joined
Swansea City on a free transfer on 8 July 2021; he signed a three-year contract.
Hull City (loan) On 31 January 2022, Walsh joined
Hull City on loan until the end of the 2021–22 season. He made his debut on 8 February, in the away match against
Derby County. Walsh left Swansea when his contract expired at the end of the
2023–24 season.
Luton Town On 20 August 2024, following a trial period with the club, Walsh joined Championship side
Luton Town. On 12 April 2026, he started in the squad that won the
2026 EFL Trophy final. ==International career==