Background The BNT162b2 mRNA vaccine has been shown to be effective at preventing serious Covid-19 events in clinical trials . There is less evidence on effectiveness in real-world settings, especially for older people . The rapid roll-out of the NHS vaccination programme in England based on age thresholds offers an opportunity to make unbiased comparisons of outcomes between vaccinated and unvaccinated populations . Methods and Findings We matched older (aged 80-83 years) vaccine recipients with younger (aged 76-79 years) persons not yet eligible to receive the vaccine on gender, area of residence, area deprivation, health status, living arrangements, acute illness, and history of seasonal flu vaccination . We also adjusted for the over-representation of Covid-19 positive individuals in the control population because eligibility for vaccination required no Covid-19 symptoms in the previous two weeks . The study population included 170,226 individuals between the ages of 80 and 83 years from community settings outside care homes who received one dose of BNT162b2 mRNA between the 15th and 20th December 2020 and were scheduled a second dose 21 days later . We found emergency hospital admissions were 51.0% (95% confidence interval : 19.9% to 69.5 %) lower and positive Covid-19 tests were 55.2% (40.8% to 66.8 %) lower for vaccinated individuals compared to matched controls 21 to 27 days after first vaccination . Emergency admissions were 75.6% (52.8% to 87.6 %) lower and positive Covid-19 tests were 70.1% (55.1% to 80.1 %) lower 35 to 41 days after first vaccination when 79% of participants had received a second dose within 26 days of their first dose . Conclusions Receipt of the BNT162b2 mRNA vaccine is effective at reducing Covid-19 hospitalisations and infections . The nationwide vaccination of older adults in England with the BNT162b2 mRNA vaccine reduced the burden of Covid-19.