Early changes in lung cancer care can affect survival. Given the decrease in diagnosis during lockdowns, we calculated their impact on survival using National Lung Cancer Audit data. Percentage survival and HRs for death were compared between 2019 and lockdown periods of 2020. Decreased survival was observed from the first national lockdown onwards and within 90 days of diagnosis. HRs were highest for people diagnosed at the end of 2020 at 1.26 (95% CI 1.20 to 1.32) for death within 90 days and 1.51 (95% CI 1.42 to 1.60) for death between 91 and 270 days. Further work is needed on measures to mitigate this impact.