This study investigates regional variations in the factors associated with acceptance and actual experience of intimate partner violence (IPV) among married women in northern and southern Nigeria - two regions with distinct socio-cultural and economic differences. Data from the 2018 demographic and health survey are analysed to compare these two regions. The sample comprised married/living-with-partner women within the reproductive age of 15-49. Overall, a positive association exists between IPV experience and IPV acceptance, regardless of which is used as the outcome variable. Contrary to the notion that IPV is prevalent where its acceptance is high, this study finds that the reverse is true. IPV acceptance is significantly higher in the north than in the south (39.4% versus 14.7%), but the reverse is the case for the actual experience of IPV (20.1% versus 24.7%). Being employed and having access to the internet reduce the odds of IPV victimisation for women in the south, but increases the chances for northern women. Muslims in the north have significantly higher odds of IPV acceptance than their Christian counterparts in the same region, but the reverse is the case in the south. Regional differences also exist in the influence of decision-making, educational difference between spouses, and media exposure. While the cosmopolitan-success and conservative-failure hypothesis explains the regional differences in the acceptance of IPV, it fails to explain differences in the actual experience of IPV. The study provides alternative explanations for the regional differences in the experience of IPV and acceptance of it in Nigeria, and it points to the need for differing intervention programmes across regions. Notably, the study found that the association between justification of IPV and actual experience of it is bi-directional and suggests caution in making causal inferences.