Relationships can get messy, particularly when you realize your partner of only a few months might have the right to half of your assets in Brazil. That car you bought? Yup, that could be hers. The house? That too.

In the US, we often think of this in the context of common law marriage. In Brazil, the closest concept would be união estável. Brazilian law defines união estável as a continuous and lasting public union with the purpose of forming a family.

União estável isn’t really marriage. In fact, technically you’re not married. But the legal consequences are basically the same when we think about the right to assets and inheritance. That's because the default marital property regime that applies to a união estável is comunhão parcial de bens (similar to the community property regime in the US).

How do you know if you’re in a união estável? Well, that would be up to a court to decide, but think about whether you live together, plan to adopt or have kids, or share finances. The closer it looks to marriage, the more likely you’re in a união estável.

If you’re concerned, consider filing a public deed where you and your partner declare that you’re in a união estável. That way you can choose your property regime rather than relying on the default. Think of it like signing a prenup.

Looking for other options? Check out our next article about contratos de namoro. Perhaps it's a better option for you.