OBJECTIVE: To assess the association between timing of maternal combination ART (cART) initiation and stillbirth among HIV-infected pregnant women in Malawi's Option B+ programme. METHODS: Cohort study of HIV-infected pregnant women delivering singleton live or stillborn babies at ≥28 weeks of gestation using routine data from maternity registers between 1 January 2012 and 30 June 2015. We defined stillbirth as death of a foetus at ≥28 weeks of gestation. We report proportions of stillbirth according to timing of maternal cART initiation (before pregnancy, 1st or 2nd trimester, or 3rd trimester or labour). We used logistic regression, with robust standard errors to account for clustering of women within health facilities, to investigate the association between timing of cART initiation and stillbirth. RESULTS: Of 10 558 mother-infant pairs abstracted from registers, 8380 (79.4%) met inclusion criteria. The overall rate of stillbirth was 25 per 1000 deliveries (95% confidence interval 22-29). We found no significant association between timing of maternal cART initiation and stillbirth. In multivariable models, older maternal age, male sex of the infant, breech vaginal delivery, delivery at < 34 weeks of gestation and experience of any maternal obstetric complication were associated with higher odds of stillbirth. Deliveries managed by a mission hospital or health centre were associated with lower odds of stillbirth. CONCLUSION: Pregnant women's exposure to cART, regardless of time of its initiation, was not associated with increased odds of stillbirth.