As the prevalence of cohabitation increases in many countries understanding of how cohabiting couples manage household finances, and how their behaviour compares to their married peers, has become a topic of increasing importance. Studies in most countries find a ‘cohabitation gap’ with cohabiting couples being less likely to pool their incomes and act as a single economic unit compared to married people. It is often hypothesised that in countries where cohabitation is more widespread and socially accepted as an alternative to marriage, that cohabitors would behave more similarly to married people when it came to sharing or pooling of income within the household. However, rather surprisingly existing cross-national research comparing income pooling in married and cohabiting couples does not find variation in the ‘cohabitation gap’ across countries. In this paper we extend upon existing research, using multilevel modelling and a larger number of countries to examine cross-national differences in income pooling between married and cohabiting people. We find that in some countries cohabiting and married couples act very similarly in terms of their income organization, whereas in others there is a large difference in the income management behaviour of married and unmarried couples. In other words, the size of the cohabitation gap does vary across countries, and that economic constraints and welfare regime are associated with this cohabitation gap.