OBJECTIVE: Our purpose was to explore maternal actigraphically measured sleep, subjective sleep reports, and daytime functioning on the basis of current feeding method status during postpartum weeks 2 through 12. METHODS: Objectively measured total sleep time, sleep efficiency, and fragmentation, subjectively reported numbers of nocturnal awakenings, total nocturnal wake time, and sleep quality, and sleepiness/fatigue measured by using the fatigue visual analog scale, the Stanford Sleepiness Scale, or the Epworth Sleepiness Scale were assessed. RESULTS: We did not find differences between women who were exclusively breastfeeding, exclusively formula feeding, or using a combination of the 2 methods, with respect to the assessed parameters. CONCLUSIONS: Efforts to encourage women to breastfeed should include information about sleep. Specifically, women should be told that choosing to formula feed does not equate with improved sleep. The risks of not breastfeeding should be weighed against the cumulative lack of evidence indicating any benefit of formula feeding on maternal sleep.