Article 1083(3) of the Civil Code, as amended by Law 13/2019 of 12 February, provides that a landlord cannot be required to maintain the lease "in the event of arrears equal to or exceeding three months in the payment of rent".
Before that amendment the threshold was two months. Templates downloaded from the internet — including some still available today — keep the old wording.
Practical consequence: a clause allowing termination after two months of arrears does not hold against the tenant. A landlord acting on it risks having the eviction refused and losing several more months.
The clauses generated by this tool follow the wording currently in force.
Source：https://www.pgdlisboa.pt/leis/lei_mostra_articulado.php?nid=775&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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