Objective. This study aims to explore and analyze the modern contraceptive use of National Health Insurance (NHI) participants before and during the COVID-19 pandemic in South Kalimantan, Indonesia. Methods. This research is an ecological study using aggregated data from 13 Districts/Cities in South Kalimantan. This study used secondary data in 2018-2020 from the official website of the National Population and Family Planning Agency. Spatial analysis and paired T-test were used. Results. There were 30.7% of Districts/Cities in stagnation and 30.7% in the decline of modern contraception use during the pandemic (2019-2020). In addition, the study showed that there were differences in the use of modern contraception before (2019) and during the COVID-19 pandemic (2020) among active family planning acceptors of NHI participants (p=0.048). Conclusion. The existence of NHI, especially recipients of contribution assistance, can increase the use of modern contraception in South Kalimantan. There are differences in the use of modern contraception before and during the COVID-19 pandemic among NHI participants. © 2024 University of the Philippines Manila. All rights reserved.