In this paper, I present differences in income, intra-household inequality and tax planning between mixed and same-sex couples. By using unique administrative tax data, I find that household incomes of same-sex couples are significantly higher than those of heterosexual couples. While there is no difference in intra-household inequality between heterosexual couples and male same-sex couples, lesbian couples have significantly lower intra-couple income inequality. This is in line with previous research. When it comes to tax planning, there are major differences between heterosexual couples and homosexual couples. While tax planning in heterosexual couples often leads to a high marginal tax burden for the secondary earner, this is not the case for same-sex couples.