Polish law does not recognize cohabitation as a relationship creating legally binding obligations between the people living together.
There are no civil partnerships in the meaning of possibility of registering such an institution governing common life of two people either of the same or different sex anywhere. Legislative work is being done on it by virtually every elected Parliament, but it has not led to any effect so far.
Of course children born in such a relationship have full rights, as there is no differentiation between children born within or outside marriage.
The problem occurs, when it comes to pecuniary or property obligations between cohabitants. Since they are not spouses, the law governing joint marital ownership or separation of goods, cannot apply.
The Supreme Court in one of its judgments ordered, that such a situation be treated as a legal obligation most similar to any existing form of contact, namely any contact, which the parties could have entered.
This is of little help when legal disputes arise. And this is normally when cohabitation breaks down.
Therefore please remember – whenever making investments in the factual relationship of cohabitation – try to enter into a contract in writing which will provide all necessary information- what sort of relation is being undertaken, what purpose it suits and how it is financed and how it is to be accounted for in the future.