The party achieved their greatest contemporary result in the 2020 Irish general election, topping the first-preference votes with 24.5% and winning 37 seats. Due to poor results in the 2019 local elections and elections to the European Parliament, the party ran only 42 candidates and did not compete in Cork North-West. The party achieved unexpected success in the early counting, with 27 candidates being elected on the first count. Party leader Mary Lou McDonald called the result a "revolution" and announced she would pursue the formation of a government including Sinn Féin. Ultimately negotiations to form a new government led to Fianna Fáil, Fine Gael and the Green Party agreeing to enter a majority coalition government in June. Sinn Féin pledged to be a strong opposition to the new coalition.