The Intervention with Microfinance for AIDS and Gender Equity (IMAGE) programme has been scaled up to three provinces in South Africa. This paper explores associations between women's engagement in the intervention, intimate partner violence (IPV) and factors associated with IPV and partner abuse. We enrolled women receiving group-based microfinance loans plus gender training into the scaled-up IMAGE cohort study (n = 860). We present cross-sectional analysis on participants' characteristics and intervention engagement and use multivariate logistic regression to explore associations. 17% of women reported lifetime (95% CI 15 to 20%) and 7% past year (95% CI 5 to 9%) IPV, 9% past-year economic (95% CI 7 to 11%) and 11% past-year emotional (95% CI 9 to 14%) abuse. Women under 35 years had higher levels of IPV and emotional abuse. 53% of women attended all the trainings, 83% continuously borrowed and 98% agreed the training had a major impact on their life. Attendance was associated with improved partner relationships (χ2p < 0.001), but not lower IPV risk. Odds of past-year IPV decreased the more types of support (e.g. advice) women received from group members (aOR 0.27, p < 0.001 among those reporting all support versus none or some). A similar pattern was seen for economic, but not emotional, abuse. The scaled-up IMAGE intervention is widely acceptable and may support improvements in partner relationships, but younger women need to be targeted. Group support appears to be a potentially important component of the intervention.