Ahannach started his professional career with
Eerste Divisie side
Almere City, before moving on to England. On 10 August 2017, Ahannach signed for
Premier League club
Brighton & Hove Albion on a five-year contract. He was loaned out to
Sparta Rotterdam of the
Eredivisie for the 2017–18 season where he scored once in twelve appearances. Ahannach signed for
Belgian second tier side
Union SG on 2 September 2019 on a season-long loan. On 2 February 2021, it was announced that Ahannach had signed with
FC Den Bosch. The move reunited him with
Jack de Gier, his manager at Almere City. On 9 June 2022, Ahannach joined Saudi Arabian side
Al-Arabi. On 2 January 2023, Ahannach joined
Al-Rawdhah on loan. In August 2023, Ahannach joined Moroccan side
Wydad AC. ==International career==