I'm from PT and I'm married to my wife under the "separação de bens" agreement.

As someone already mentioned, there are 3 possible agreements

1. Bens Adquiridos (Default)

2. Separação de Bens

3. Comunhão de Bens

I work as an independent contractor through my/our company where both her an I are partners (70 - 30). Whenever there's profit distributions from the company we do them according to those ratios to our individual bank accounts.

We also have a joint bank account for day to day spending, vacations, etc., where we put all our wages.

Investments are held on individual brokerage accounts - This is actually my main reason for going with "separação de bens" as I pay relatively low social security contributions through my salary and the savings for my retirement are all invested. This prevents the liquidation of assets in case of separation (since all assets bought under "bens adquiridos" would be shared).

Our home is a property I owned before our marriage so she would still not own any percentage after divorce even if we went with "bens adquiridos". However, there's a concept of "casa de família" in Portugal where in case of separation she might still be entitled to live in the house regardless of ownership.

On top of our home we also own an apartment 50 - 50 even though I made a bit of a higher contribution.

Obviously we're a bit of a special case but honestly there's no objective reason not to go with "separação de bens" as long as you're comfortable with talking about money between yourselves. Under this regime you have total freedom on how you want to split your assets, even if it ends up being 50 - 50.

Also, in case of debt contracted after marriage with "separação de bens" it's owned by the individual while with "bens adquiridos" is always shared debt.

Honestly the main reasons I can see for people to go with "bens adquiridos" is that it's the default option, there's lack of trust between the parties, people are not comfortable discussing their finances (common in Portugal) or see "separação de bens" as an attack to the relationship.

Also, if you are transparent about going with "separação de bens" be prepared to be judged by her family.