This study aimed to assess the coverage of essential postnatal maternal care services among women residing in the slums of Islamabad. A community-based, cross-sectional study was conducted to assess the coverage of essential postnatal care (PNC) services. Using random sampling, 416 women living in the squatter settlements of Islamabad Capital Territory were selected as study participants. Data was analyzed by using SPSS version 22. Descriptive statistics were employed to display frequencies for categorical variables, whereas mean, median, and standard deviation were calculated for continuous variables. The analysis of data showed that 93.5 percent of the women utilized postnatal services at least once after delivery. Approximately 9 percent and 4 percent of women received all eight recommended services within 24 h of birth and beyond 24 h of birth, respectively. Effective PNC services were received by only 1 percent of the women. The study revealed that the utilization of effective PNC was very low. The majority of the women delivered in health institutions and received their first PNC checkups, but follow-up for the recommended checkups was very low. These results can help health professionals and policymakers in designing programs and developing efficient strategies that would improve PNC service utilization in Pakistan.