The court ruled that legally differentiating the two types of partnership violated Germany’s guarantee of equal rights, and mandated the ruling be retroactively applied to the introduction of the registered partnership system in 2001.
Married couples in Germany are able to jointly declare their annual income, lowering their overall tax burden.
German Chancellor Angela Merkel has been opposed to tax reform for registered partners, her party claiming tax benefits were to support heterosexual married couples because they were more likely to have children.
Public reaction to the reform has been positive, with most major German newspapers applauding the decision.
Since their introduction, registered partners have been granted marriage-like protections in a series of legal reforms, gaining equality of pension entitlements, adoption rights and inheritance tax rates.
Chancellor Merkel’s conservative Christian Democratic Union is opposed to marriage equality, despite party-internal dissent on the issue and widespread public support for a change to Germany’s marriage laws.