We describe the management of two linked severe acute respiratory coronavirus 2 (SARS-CoV-2) outbreaks, predominantly amongst 18-35-year-olds, in a UK county in July-to-September 2021, following the lifting of national coronavirus disease 2019 (COVID-19)-associated social restrictions. One was associated with a nightclub and one with five air force bases. On week beginning 2nd August 2021, air force contact tracing teams detected 68 cases across five bases within one county; 21 (30.9%) were associated with a night-time economy venue, 13 (19.1%) with night-time economy venues in the county's main town and at least one case per base (n = 6, 8.8%) with a particular nightclub in this town, which itself had been associated with 302 cases in the previous week (coinciding with its reopening following a national lockdown). In response, Public Health England/United Kingdom Health Security Agency, air force and local authority teams collaboratively implemented communication strategies and enhanced access to SARS-CoV-2 testing and vaccination. Key challenges included attempting to encourage behaviours that reduce likelihood of transmission to a population who may have considered themselves at low risk from severe COVID-19. This report may inform future preparation for, and management of, easing of potential future pandemic-related social restrictions, and how an outbreak in this context may be addressed.