One of the primary contributors to the ambient air pollution in Ulaanbaatar is the combustion of raw coal and briquettes in ger areas. The pollution caused by the combustion process also significantly impacts indoor air quality, resulting in severe implications for people’s health. This study, designed and implemented by the nonprofit organization Breathe Mongolia – Clean Air Coalition, aimed to assess indoor air pollution in gers that had installed Cooking, Heating and Insulation Packages (CHIPs)—an initiative that provides electrical heating and cooking and insulation material at a subsidized rate. 28 gers participated in the study—25 with CHIPs and three without for comparison. We used low-cost technology to measure carbon monoxide (Binary System monitors) in all 28 gers and fine particulate matter (AirVisual monitors) in 14 gers. The data acquisition took place during the winter season of 2022-2023. The highest PM_2.5 concentration was 279.09 μg/m³ in the evening and the highest weekday level was 248.70 μg/m³ on Fridays. The highest carbon monoxide concentration was 20.62 ppm in the evening and 16.08 ppm Thursdays. For a comprehensive assessment of indoor air quality in gers and to gauge the effectiveness of interventions like CHIPs in reducing indoor air pollution, Breathe Mongolia will continue its monitoring efforts in ger areas. Through such efforts, we hope to address data scarcity and help evaluate what interventions are needed to improve indoor air quality.