While just over one in three heterosexual women will experience intimate partner violence (IPV) in her lifetime, 61% of bisexual women and 78% of non-monosexual women will. Combining previous research and theories on power, social resources, binegativity, and gender-based violence, this article analyzes the role of power and inequality in non-monosexual women's IPV victimization. Using data from the National Intimate Partner and Sexual Violence Survey, this article first examines rates of IPV victimization for statistically significant differences between monosexual (e.g., only have dating, romantic, and sexual partners of one sex/gender) and non-monosexual (e.g., have dating, romantic, and sexual partners of multiple sexes/genders) women in the United States and, second, introduces theoretically important variables to logistic regression analyses to determine the correlates of IPV victimization among non-monosexual women (age, race ethnicity, income, education, immigration status, and indigeneity; partner gender; sexual identity). Findings indicate that non-monosexual women are more likely to experience sexual, emotional, and psychological/control violence, and intimate stalking, but have an equivalent risk of experiencing physical violence. Moreover, having an abusive partner who is a man, having a lot of relative social power, and self-identifying as "bisexual" are all significant factors in violence victimization. Importantly, this is the first study using nationally representative data that confirms non-monosexual women are particularly at risk for sexual identity-based violence at the hands of their male/man partners, suggesting binegativity and biphobia may indeed be linked to hegemonic masculinity. Suggestions for moving research forward include improving data collection efforts such that we can disentangle gender from sex and individual aggregate power from relationship inequalities, as well as more adequately account for the timing of sexual identity disclosures within relationships, relative to the timing of violent episodes.