Sociodemographic disparities in COVID-19 seroprevalence across England in the Oxford RCGP primary care sentinel network

•We present a serological survey of COVID-19 infections in England.•This study used sera collected alongside routine blood tests in primary care.•Seropositivity was higher in younger age and in Black and Asian ethnicities.•And also higher in major conurbations and in non-smokers.•We found no difference by deprivation, sex or shielding recommendation.