Maignan played for France at every level from under-16 to under-21. He captained the under-17 side at the 2012 European Championship in Slovenia. He received his first senior call-up in May 2019, ahead of UEFA Euro 2020 qualifiers against Turkey and Andorra and a friendly with Bolivia. He made his debut on 7 October 2020 as a half-time substitute for Steve Mandanda in a friendly against Ukraine, which ended as a 7–1 win at the Stade de France. In May 2021, he was called up for the delayed Euro 2020 finals.