Same-sex couples have been the subject of intense media and political discussion in relation to formal rights to marry and raise children. However, we still know comparatively little about the family outcomes of individuals from sexual minorities. We investigate the quality of the intimate relationships of heterosexual, gay/lesbian and bisexual individuals in Australia and the UK. We contribute to previous research by considering bisexual individuals and mixed-orientation couples, and using recent, large and nationally-representative cross-national data. We find that relationship quality in same-sex couples is as high as, if not higher than, in heterosexual couples. This suggests that policies to legalise same-sex marriage are well-guided and sexual minority couples are well-placed to raise children in warm and loving environments. Another key finding is that the lowest relationship quality in both Australia and the UK is reported by bisexual individuals, which highlights the need to pay further attention to this subgroup.