BACKGROUND: Contraceptive services were significantly disrupted during the COVID-19 pandemic in Britain. We investigated contraception-related health inequalities in the first year of the pandemic. METHODS: Natsal-COVID Wave 2 surveyed 6658 adults aged 18-59 years between March and April 2021, using quotas and weighting to achieve quasi-representativeness. Our analysis included sexually active participants aged 18-44 years, described as female at birth. We analysed contraception use, contraceptive switching due to the pandemic, contraceptive service access, and pregnancy plannedness. RESULTS: Of 1488 participants, 1619 were at risk of unplanned pregnancy, of whom 54.1% (51.0%-57.1%) reported routinely using effective contraception in the past year. Among all participants, 14.3% (12.5%-16.3%) reported switching or stopping contraception due to the pandemic. 3.2% (2.0%-5.1%) of those using effective methods pre-pandemic switched to less effective methods, while 3.8% (2.5%-5.9%) stopped. 29.3% (26.9%-31.8%) of at-risk participants reported seeking contraceptive services, of whom 16.4% (13.0%-20.4%) reported difficulty accessing services. Clinic closures and cancelled appointments were commonly reported pandemic-related reasons for difficulty accessing services. This unmet need was associated with younger age, diverse sexual identities and anxiety symptoms. Of 199 pregnancies, 6.6% (3.9%-11.1%) scored as 'unplanned'; less planning was associated with younger age, lower social grade and unemployment. CONCLUSIONS: Just under a third of participants sought contraceptive services during the pandemic and most were successful, indicating resilience and adaptability of service delivery. However, one in six reported an unmet need due to the pandemic. COVID-induced inequalities in service access potentially exacerbated existing reproductive health inequalities. These should be addressed in the post-pandemic period and beyond.