Little is known about prenatal breastfeeding confidence, although such knowledge is necessary for developing the content of counseling and tailoring it for individuals. The purpose of this study was to describe women’s prenatal breastfeeding confidence and how their sociodemographic characteristics, breastfeeding knowledge, and attitudes relate to it. The electronic confidence scale was used in data collection, and 123 Finnish women filled in the questionnaire. The mean confidence score was 83.88 when the maximum possible score was 120. Confidence scores varied when parity, breastfeeding knowledge, and attitudes were involved. Variables regarding breastfeeding as difficult, regarding breastfeeding as exhausting, and parity explained 38.1% of the variation of the breastfeeding confidence scores. Pregnant women need information about managing potential breastfeeding problems and the physiology of breastfeeding. Interventions designed to promote breastfeeding confidence need to be focused on primiparas and women with a lack of breastfeeding knowledge.