According to De Telegraaf's Mike Verweij, the move includes an option for a further year, bringing an end to a two-week search for a new club since leaving Tottenham Hotspur when his contract expired at the end of last season.
Ajax had first been linked with Bissouma earlier in the summer via an African outlet, but did not follow through on the interest at the time, before returning for the 30-year-old with the transfer window already closed.
The defensively minded midfielder made 111 appearances for Tottenham after Spurs signed him from Brighton & Hove Albion four years ago for around €30 million. His time in north London ended without a contract renewal following a 2024 incident in which he shared a video on Snapchat showing him inhaling nitrous oxide from a balloon, a breach that saw Tottenham suspend him for a match against Leicester City.
Bissouma apologised at the time, describing it as a "serious lapse in judgement." He made just 11 Premier League appearances last season as he fell down the pecking order under Spurs' coaching changes.
Ajax are looking to hand the Mali international a fresh opportunity as they continue an ambitious summer of recruitment under sporting director Jordi Cruyff, who is understood to be personally keen on the deal. The Amsterdam club have already brought in a batch of new faces this year, with Sofyan Amrabat, Daley Blind, Joffrey Torrents and Julian Brandt arriving as free agents, while Tolu Arokodare, Thilo Kehrer, Marc-Andre ter Stegen and Simon Adingra joined on loan deals.
Ajax also paid transfer fees for Viktor Tsygankov (€3 million), Caio Henrique (€10 million) and Marcos Leonardo (€20 million).
Should the move be completed, Bissouma would add further depth and experience to an Ajax midfield already reshaped over the summer, giving the club another option in a holding role as they pursue silverware on multiple fronts this season.
Ajax face competition from elsewhere in Europe's top leagues for Bissouma's signature, with the midfielder having drawn interest since becoming a free agent, though talks with other suitors are understood to have stalled. His arrival would provide competition for Amrabat in the club's deepest midfield role, an area sporting director Jordi Cruyff has identified as needing further depth given Ajax's commitments across multiple competitions this season.