Celtic
On 31 December 2021, it was announced that Maeda had signed for Scottish Premiership club Celtic on loan for the rest of the season, with an obligation to buy at the end of the loan. On 17 January 2022, Maeda made his debut for Celtic and scored his first goal in the fourth minute, in a league fixture against Hibernian at Celtic Park. Maeda signed a four-year contract with Celtic at the end of the season, when his move was made permanent.
On 6 September 2022, Maeda came on as a half-time substitute for Liel Abada to make his UEFA Champions League debut in a 3–0 home defeat against Real Madrid. On 2 January 2023, he scored the opening goal in a 2–2 draw at Rangers. His form at this time saw Premier League side Southampton monitor him.
On 6 July 2023, Maeda signed a new four-year contract with Celtic, keeping him at the club until 2027.
Maeda had his most prolific season during 2024–25, scoring over 30 goals, with his form particularly picking up from January. He scored his first Champions League goal against Slovan Bratislava, and scored a further three against Borussia Dortmund, Club Brugge and Bayern Munich. This put him level with Shinji Kagawa and Takumi Minamino for most goals by a Japanese player in the Champions League. It also made him the first player to score four goals for Celtic in UEFA competition since Joe Craig in the 1977–78 season.
Upon scoring against Kilmarnock on 12 April 2025, he became the first Celtic player to score in eight consecutive starts at Parkhead since Henrik Larsson in 2004. Celtic fans also began singing Maeda's name to the tune of "Tequila" by the Champs.
Maeda was named as one of four nominees for the 2024–25 PFA Scotland Players' Player of the Year, alongside teammates Callum McGregor and Nicolas Kühn, and Dundee striker Simon Murray.
In August 2025, it was reported that Maeda wanted to leave Celtic but could not as the club did not have time to buy a backup. This led to poor form in the months of September and October, with Maeda only scoring two goals.
In the closing stages of the 2025–26 season, Maeda scored in five consecutive league matches, including a stunning overhead against Rangers and the decisive second goal in the 87th minute of a 3–1 victory over Hearts on 16 May 2026, the final matchday, helping secure his club's record 56th league title. He also scored the opening goal in the Scottish Cup final against Dunfermline the following week, lobbing goalkeeper Aston Oxborough from the edge of the penalty box.
