Comodato

A loan-for-use contract: the owner lets you live in their property free of charge. It is a proper contract type under Portuguese civil law, not an informal arrangement.

It matters at AIMA. If you live with relatives or friends and pay nothing, you have no lease to show — and a comodato contract plus the land-registry certificate is accepted as proof of accommodation. It is the clean way out of the situation where you genuinely live somewhere but appear on no document.

See also comprovativo de alojamento for what AIMA accepts when even this is not available.