The 2021 Toronto Argonauts season was the 63rd season for the team in the Canadian Football League and their 148th year of existence. The Argonauts improved on their 4-14 record from their previous season in 2019 with a win in week 10 against the Ottawa Redblacks on October 6, 2021. The team qualified for the playoffs for the first time since 2017, on October 30, 2021, with a win over the BC Lions. The Argonauts then clinched first place in the East Division after defeating the Hamilton Tiger-Cats on November 12, 2021. However, the Argonauts lost to the same Tiger-Cats in the East Final after holding a 12–0 halftime lead, but were unable to score a touchdown and lost 27–19.