Cross-sectional surveys have found variations in how prepared medical students feel to prescribe antibiotics responsibly, but insights are lacking on the stability of these outcomes. In a 2015 survey, final-year Swedish medical students reported very high preparedness levels across a comprehensive range of relevant curriculum topics. We repeated this survey in 2021 to assess the stability of previous findings and to capture the potential impacts of the COVID-19 pandemic. Final-year students in 2015 and 2021 at all seven Swedish medical schools were eligible to participate in an online survey covering curricula topics, teaching methods and COVID-19 impacts (2021). Eligible students received email invitations and reminders from local coordinators. Students from six of seven medical schools participated in both surveys, with response rates of 24.1% (309/1281) in 2021 and 21.3% (239/1124) in 2015. The average global preparedness was 77.0% and 83.2%, respectively (p < 0.001), with lower preparedness levels in 24/27 curriculum topics in 2021. Students at certain universities reported COVID-19 impacts on antibiotic prescribing education (format, duration and perceived quality). Self-reported preparedness levels have fallen slightly but remain high compared with 2015 levels in other European countries. Students consistently reported lower preparedness in specific topics; improvement efforts should consider focusing on these areas, particularly in the context of the ongoing implementation of programmes leading to a full licence upon graduation.