SHL Aho played as a youth with
IF Björklöven before moving the fellow Swedish club
Skellefteå AIK. Aho made his
Elitserien debut on the blueline in 1 game with Skellefteå AIK during the
2012–13 season. He was signed to a new four-year contract with the club on Tuesday, 28 May 2013. After helping Skellefteå AIK claim a second straight championship, Aho was rated amongst the top 10 European skaters for the
2014 NHL entry draft. Despite this, Aho was passed over due to his diminutive size and returned to continue with Skellefteå AIK. After his first full SHL season in
2014–15, helping the club return to the finals for the third-consecutive season with 9 points in 41 games, Aho was again rated amongst the top 15 skaters for the
2015 NHL entry draft.
New York Islanders Aho was eventually drafted in his fourth eligible draft as an average prospect by the
New York Islanders in the fifth round, 139th overall, of the
2017 NHL entry draft on 24 June 2017. He agreed to a three-year entry-level contract with the Islanders on 5 July 2017. Aho was assigned to the Islanders'
American Hockey League (AHL) affiliate, the
Bridgeport Sound Tigers to begin the
2017–18 season after attending training camp. He was recalled to the NHL on 28 December, and played his first NHL game in a 6–1 loss against the
Colorado Avalanche on 31 December. He scored his first NHL goal in a 5–4 win over the
New Jersey Devils on 7 January 2018. After attending the Islanders training camp prior to the
2018–19 season, Aho was assigned to the Sound Tigers. On 3 January 2019, Aho and teammate
Michael Dal Colle were selected to represent the Sound Tigers at the 2019
AHL All-Star Classic.
Pittsburgh Penguins Following seven seasons within the Islanders organization, Aho left as a free agent and was signed to a two-year, $1.55 million contract with the Pittsburgh Penguins on July 2, 2024. == Personal life ==