<jats:title>Abstract</jats:title><jats:sec><jats:title>Background</jats:title><jats:p>Ethnic minorities have experienced disproportionate COVID-19 mortality rates. We estimated associations between household composition and COVID-19 mortality in older adults (≥ 65 years) using a newly linked census-based dataset, and investigated whether living in a multi-generational household explained some of the elevated COVID-19 mortality amongst ethnic minority groups.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>Using retrospective data from the 2011 Census linked to Hospital Episode Statistics (2017-2019) and death registration data (up to 27<jats:sup>th</jats:sup> July 2020), we followed adults aged 65 years or over living in private households in England from 2 March 2020 until 27 July 2020 (n=10,078,568). We estimated hazard ratios (HRs) for COVID-19 death for people living in a multi-generational household compared with people living with another older adult, adjusting for geographical factors, socio-economic characteristics and pre-pandemic health. We conducted a causal mediation analysis to estimate the proportion of ethnic inequalities explained by living in a multi-generational household.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Living in a multi-generational household was associated with an increased risk of COVID-19 death. After adjusting for confounding factors, the HRs for living in a multi-generational household with dependent children were 1.13 [95% confidence interval 1.01-1.27] and 1.17 [1.01-1.35] for older males and females. The HRs for living in a multi-generational household without dependent children were 1.03 [0.97 - 1.09] for older males and 1.22 [1.12 - 1.32] for older females. Living in a multi-generational household explained between 10% and 15% of the elevated risk of COVID-19 death among older females from South Asian background, but very little for South Asian males or people in other ethnic minority groups.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>Older adults living with younger people are at increased risk of COVID-19 mortality, and this is a notable contributing factor to the excess risk experienced by older South Asian females compared to White females. Relevant public health interventions should be directed at communities where such multi-generational households are highly prevalent.</jats:p></jats:sec><jats:sec><jats:title>Funding</jats:title><jats:p>This research was funded by the Office for National Statistics.</jats:p></jats:sec>