Estimating global lives and life-years saved is important to put into perspective the benefits of COVID-19 vaccination. Prior studies have focused mainly on the pre-Omicron period or only on specific regions, lack crucial life-year calculations, and often depend on strong modeling assumptions with unaccounted uncertainty. We aimed to calculate the lives and life-years saved by COVID-19 vaccination worldwide from the onset of the vaccination campaigns and until October 2024. We considered different strata according to age; community-dwelling and long-term care residence status; pre-Omicron and Omicron periods; and vaccination before and after a SARS-CoV-2 infection. In the main analysis, 2.533 million deaths were averted. Eighty-two percent were among people vaccinated before any infection, 57% were in the Omicron period, and 90% pertained to people 60 years and above. Sensitivity analyses suggested 1.4 to 4.0 million lives saved. Some sensitivity analyses showed preponderance of the benefit during the pre-Omicron period. We estimated 14.8 million life-years saved (sensitivity range, 7.4-23.6 million life-years). Most life-years saved (76%) were in people over 60 years old, but long-term care residents contributed only 2% of the total. Children and adolescents (0.01% of lives saved and 0.1% of life-years saved) and young adults 20-29 years old (0.07% of lives saved and 0.3% of life-years saved) had very small contributions to the total benefit. Based on a number of assumptions, these estimates are substantially more conservative than previous calculations focusing mostly on the first year of vaccination, but they still undeniably demonstrate a major overall benefit from COVID-19 vaccination during 2020-2024. The vast majority of benefit in lives and life-years saved was secured for a portion of the elderly minority of the global population. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement The study did not receive any funding ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data are in the manuscript

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