INTRODUCTION: In 2020-2022, the maternal mortality rate in the United Kingdom rose to its highest level in nearly 20 years. This period coincided with the COVID-19 pandemic, when pregnant women were at increased risk of severe infection and death. After excluding deaths directly attributed to COVID-19, maternal mortality rates remained high, suggesting that disruptions to maternity and wider health services may have adversely affected outcomes. This study describes the patterns, causes and characteristics of maternal deaths in the UK before and during the pandemic. MATERIAL AND METHODS: The MBRRACE-UK database was used to identify all maternal deaths in the UK during or up to 6 weeks after pregnancy from 2014 to 2022. The pre-pandemic period was defined as January 2014 to February 2020 and the pandemic as March 2020 to December 2022. Data were cleaned and aggregated to permit analysis of small numbers. Maternal mortality rates and 95% confidence intervals were calculated using national maternity data as denominators. Comparisons were made between periods using chi-square tests and mortality rate ratios (RR). Analyses were conducted in Stata 17 with statistical significance set at p < 0.05. RESULTS: Maternal mortality rates were significantly higher during the pandemic compared to the pre-pandemic period (RR 1.46, 95% CI 1.25-1.71). Rates of all direct causes of maternal deaths increased during the pandemic with statistically significant increases in deaths due to thromboembolism (RR 1.69, 95% CI 1.11-2.57) and early pregnancy-related causes (RR 2.39, 1.02-5.61). During the pandemic, a greater proportion of women who died had mental health problems or experienced domestic abuse; a smaller proportion had pre-existing medical problems. Persistent inequalities were observed in maternal mortality rates for women living in deprived areas or belonging to ethnic minority groups. CONCLUSIONS: These findings indicate that the effects of the COVID-19 pandemic, including changes to service provision, were associated with increased rates of direct maternal death, underscoring the importance of maintaining equitable access to essential maternity services during future crises. The greater prevalence of mental health and social complexities amongst the women who died during the pandemic further highlights the need to improve equity in access and strengthen integrated maternity services.