OBJECTIVE: To determine the impact of the COVID-19 pandemic on diagnostic and treatment activity in 2020 across hospital providers of prostate cancer (PCa) care in the English National Health Service. METHODS: Diagnostic and treatment activity between 23 March (start of first national lockdown in England) and 31 December 2020 was compared with the same calendar period in 2019. Patients newly diagnosed with PCa were identified from national rapid cancer registration data linked to other electronic healthcare datasets. RESULTS: There was a 30.8% reduction (22 419 vs 32 409) in the number of men with newly diagnosed PCa in 2020 after the start of the first lockdown, compared with the corresponding period in 2019. Men diagnosed in 2020 were typically at a more advanced stage (Stage IV: 21.2% vs 17.4%) and slightly older (57.9% vs 55.9% ≥ 70 years; P < 0.001). Prostate biopsies in 2020 were more often performed using transperineal (TP) routes (64.0% vs 38.2%). The number of radical prostatectomies in 2020 was reduced by 26.9% (3896 vs 5331) and the number treated by external beam radiotherapy (EBRT) by 14.1% (9719 vs 11 309). Other changes included an increased use of EBRT with hypofractionation and reduced use of docetaxel chemotherapy in men with hormone-sensitive metastatic PCa (413 vs 1519) with related increase in the use of enzalutamide. CONCLUSION: We found substantial deficits in the number of diagnostic and treatment procedures for men with newly diagnosed PCa after the start of the first lockdown in 2020. The number of men diagnosed with PCa decreased by about one-third and those diagnosed had more advanced disease. Treatment patterns shifted towards those that limit the risk of COVID-19 exposure including increased use of TP biopsy, hypofractionated radiation, and enzalutamide. Urgent concerted action is required to address the COVID-19-related deficits in PCa services to mitigate their impact on long-term outcomes.