Article 3(2) of Decree-Law 160/2006 provides that the applicable regulations and "a document describing the state of repair of the premises and its dependencies, as well as of the building" must be annexed to the contract and signed by the parties.
The same paragraph adds that, in the absence of that document or in case of omission or doubt, Article 1043(2) of the Civil Code applies — meaning the premises are presumed to have been delivered in good condition.
In practice this is what settles disputes over the deposit at the end of the lease. Without a signed inventory, a landlord wanting to deduct for damage must prove the damage was not there at the start.
Note the essential point: the document must be signed. An inventory attached but unsigned does not satisfy the rule.
Source：https://www.pgdlisboa.pt/leis/lei_mostra_articulado.php?nid=2529&tabela=leis
This text is a summary of the law and does not constitute legal advice. For your specific situation, consult a lawyer admitted in Portugal.
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