The Ghanaian government began implementing the National Health Insurance Scheme (NHIS) in 2005, anchored on the universal health coverage principle. However, informal sector workers contribute to the low enrolment into the scheme. This paper examines the factors that influence enrolment status in Ghana's NHIS among individuals in the informal sector. The study employed the fixed-effects logit model, using the Ghana Socioeconomic Panel Survey datasets. The findings revealed that gender, age, education, marital status, household size, physical activity, income, savings and subjective social welfare determine enrolment decisions of persons in the informal sector. Drivers of NHIS enrolment for male and female household heads were secondary education and household size. Heterogeneously, age, Junior High School education, married, physical activity, subjective social welfare and savings influenced only male-headed households' enrolment status. The study shows differences in enrolment status among rural and urban residents, as age, education, marital status, household size, and physical activity influenced rural residents, while for urban inhabitants', savings determined their NHIS enrolment decisions. However, gender, obesity, income and subjective social welfare predicted enrolment decisions for rural and urban residents. Finally, two variables, gender (male) and physical activity predicted the NHIS enrolment decision among the poor, whereas subjective social welfare and savings influenced the wealthiest enrolment decisions.