OBJECTIVES: The objectives of the study were to investigate access to free school meals (FSMs) among eligible children, to describe factors associated with uptake and to investigate whether receiving FSMs was associated with measures of food insecurity in the UK using the Coronavirus (COVID-19) wave of the UK Household Longitudinal Study. STUDY DESIGN: The study design was cross-sectional analyses of questionnaire data collected in April 2020. METHODS: Six hundred and thirty-five children who were FSM eligible with complete data were included in the analytic sample. Accessing a FSM was defined as receiving a FSM voucher or a cooked meal at school. Multivariable logistic regression was used to investigate (i) associations between characteristics and access to FSMs and (ii) associations between access to FSMs and household food insecurity measures. All analyses accounted for survey design and sample weights to ensure representativeness. RESULTS: Fifty-one percent of eligible children accessed a FSM. Children in junior schools or above (aged 8+ years) (adjusted odds ratio [AOR]: 11.81; 95% confidence interval [CI]: 5.54, 25.19), who belonged to low-income families (AOR: 4.81; 95% CI: 2.10, 11.03) or still attending schools (AOR: 5.87; 95% CI: 1.70, 20.25) were more likely to receive FSMs. Children in Wales were less likely to access FSMs than those in England (AOR: 0.11; 95% CI: 0.03, 0.43). Receiving a FSM was associated with increased odds of recently using a food bank but not reporting feeling hungry. CONCLUSIONS: In the month after the COVID-19 lockdown, 49% of eligible children did not receive any form of FSMs. The present analyses highlight that the voucher scheme did not adequately serve children who could not attend school during the lockdown. Moreover, more needs to be done to support families relying on income-related benefits, who still report needing to access a food bank. As the scheme may be continued in summer or in a potential second wave, large improvements will be needed to improve its reach.