Background The COVID-19 pandemic had a major impact on the continuity of healthcare provision. Appointments, treatments and surgeries for non-COVID patients were often delayed, with associated health losses for patients involved. Objective To develop a method to quantify the health impact of delayed elective care for non-COVID patients. Methods A model was developed that estimated the backlog of surgical procedures in 2020 and 2021 using hospital registry data. Quality-adjusted life years (QALYs) were obtained from the literature to estimate the non-generated QALYs related to the backlog. In sensitivity analyses QALY values were varied by type of patient prioritization. Scenario analyses for future increased surgical capacity were performed. Results In 2020 and 2021 an estimated total of 305,374 elective surgeries were delayed. These delays corresponded with 319,483 non-generated QALYs. In sensitivity analyses where QALYs varied by type of patient prioritization, non-generated QALYs amounted to 150,973 and 488,195 QALYs respectively. In scenario analyses for future increased surgical capacity in 2022–2026, the non-generated QALYs decreased to 311,220 (2% future capacity increase per year) and 300,710 (5% future capacity increase per year). Large differences exist in the extent to which different treatments contributed to the total health losses. Conclusions The method sheds light on the indirect harm related to the COVID-19 pandemic. The results can be used for policy evaluations of COVID-19 responses, in preparations for future waves or other pandemics and in prioritizing the allocation of resources for capacity increases.