Breastfeeding exclusivity and duration rates are lower after caesarean birth, yet the factors contributing to these are not well understood. This mixed-methods study used an anonymous online questionnaire to examine the facilitators and barriers to establishing breastfeeding as identified by Australian women after a caesarean birth. Quantitative data were reported using descriptive statistics, and multivariable models were used to determine the factors associated with breastfeeding outcomes including the timing of breastfeeding initiation, birth experience, and commercial infant formula use. Qualitative data were analysed using an inductive thematic analysis. Data were obtained for N = 961 women, of which <50% reported skin-to-skin contact during breastfeeding initiation. The barriers to breastfeeding included aspects of clinical care and reduced mobility, while unrushed care, partner support, and physical help with picking up the baby were helpful. Following a non-elective caesarean birth, women had half the odds of early breastfeeding initiation (OR = 0.50; 95% CI: 0.36, 0.68; p ≤ 0.001) and 10 times the odds to report a negative birth experience (OR = 10.2; 95% CI: 6.88, 15.43; p < 0.001). Commercial milk formula use was higher in primiparous women (OR = 2.16; 95% CI: 1.60, 2.91; p < 0.001) and in those that birthed in a private hospital (OR = 1.67; 95% CI: 1.25, 2.32; p = 0.001). Pain and reduced mobility, as well as conflicting and rushed care, negatively impacted breastfeeding after a caesarean birth, while delayed breastfeeding initiation, higher pain ratings, and negative birth experiences were more common for women that birthed by non-elective caesarean. This study adds valuable insights into the physical, emotional, and clinical care needs of women in establishing breastfeeding after a surgical birth. Clinical staffing and care should be modified to include full access to partner support to meet the specific needs of breastfeeding women after a caesarean birth.