Globally, increasing rates of facility-based childbirth enable early intervention for small vulnerable newborns. We describe health system-level inputs, current feeding, and discharge practices for moderately low birthweight (MLBW) infants (1500-<2500g) in resource-constrained settings. The Low Birthweight Infant Feeding Exploration study is a mixed methods observational study in 12 secondary- and tertiary-level facilities in India, Malawi, and Tanzania. We analyzed data from baseline facility assessments and a prospective cohort of 148 MLBW infants from birth to discharge. Anthropometric measuring equipment (e.g., head circumference tapes, length boards), key medications (e.g., surfactant, parenteral nutrition), milk expression tools, and human milk alternatives (e.g., donor milk, formula) were not universally available. MLBW infants were preterm appropriate-for-gestational age (38.5%), preterm large-for-gestational age (3.4%), preterm small-for-gestational age (SGA) (11.5%), and term SGA (46.6%). The median length of stay was 3.1 days (IQR: 1.5, 5.7); 32.4% of infants were NICU-admitted and 67.6% were separated from mothers at least once. Exclusive breastfeeding was high (93.2%). Generalized group lactation support was provided; 81.8% of mother-infant dyads received at least one session and 56.1% had 2+ sessions. At the time of discharge, 5.1% of infants weighed >10% less than their birthweight; 18.8% of infants were discharged with weights below facility-specific policy 1800g in India, 1500g in Malawi, and 2000g in Tanzania. Based on descriptive analysis, we found constraints in health system inputs which have the potential to hinder high quality care for MLBW infants. Targeted LBW-specific lactation support, discharge at appropriate weight, and access to feeding alternatives would position MLBW for successful feeding and growth post-discharge.