Introduction Early postnatal care (EPNC) utilisation is crucial for averting maternal deaths as recommended by the World Health Organisation. About 30% of women do not obtain EPNC in Ghana and no national level study have investigated the determinants of EPNC. Therefore, this study aimed at assessing factors associated with EPNC uptake among women aged 15-49 in Ghana. Materials and methods The study utilised data from the women's file of the 2014 Ghana Demographic and Health Survey (GDHS) and sampled 1,678 women aged 15-49 who had complete data on EPNC. Descriptive computation of EPNC was done. Since EPNC (which is the main outcome variable for the study) was dichotomous, the binary logistic regression was used to determine factors influencing utilisation of EPNC at 95% two-tailed confidence interval. The results were presented as adjusted odds ratio (AOR). Stata version 14.0 was used for all the analyses. Results Descriptively, the results indicated that 31% of women aged 15-49 sought EPNC. At the inferential level, women aged 40-44 were more likely to seek EPNC compared to those aged 15-19 [AOR = 3.66, CI = 1.25-10.67]. Islam women had higher odds of EPNC as compared with Christians [AOR = 1.70, CI = 1.23-2.35]. Comparatively, women of Mande ethnic group had higher propensity to seek EPNC than the Akan [AOR = 3.22, CI = 1.20-8.69]. Residents of the Greater Accra region were over 11 times probable to utilise EPNC compared with the residents of Western region. Conclusion The key determinants of EPNC were age, religion, ethnicity, marital status and region. Therefore, the Health Promotion and Education Unit and Reproductive and Child Health Department of the Ghana Health Service need to scale up EPNC sensitisation programmes and should target women aged 15-19, Christians and other category of women with less likelihood of EPNC in order to offset the disparities.