Objective: To report on the effectiveness of a standardized core Maternity Waiting Home (MWH) model to increase facility deliveries and access to reproductive health services among women living farthest from a health facility (>10km) using facility-based data. Design: Quasi-experimental design. Setting: Seven rural districts in Zambia. Population: Women delivering at 40 health facilities between June 2016 to August 2018. Methods: 20 intervention sites and 20 comparison sites were used to test if MWHs increased access to reproductive health services for women living in rural Zambia. The difference-in-differences (DID) methodology was used to examine the effectiveness of the core MWH model on our primary outcomes. Main Outcome Measures: Differences in the change from baseline to endline in the percentage of women who: 1) traveled greater than 10 km for delivery, (2) attended a postnatal visit at 6 days postpartum, and (3) were referred to a higher-level health facility between intervention and comparison group. Results: We detected a significant difference for the percentage of deliveries at intervention facilities with the core MWH model for all women living >10km away (p=0.03), adolescent women (<18 years) living >10km away (p=0.002), and primigravida women living >10km away (p=0.01). There were no significant differences for women attending a postnatal care visit at 6 days postpartum (p=0.07) or for women referred to the next level of care (p=0.29). Conclusion: The core MWH model was successful in reaching women with historically low rates of facility delivery, those living >10km from a healthcare facility, including adolescent women and primigravidas.