The taxable income is box 1 and the net tax due is box 22 of last year Portuguese tax assessment, which is what article 3(2) requires. The property tax value is on the caderneta predial and is only used for the ceiling: leave it at zero if you do not know it.

This sum assumes the home has already been allocated to you under the supported-rent regime. The access conditions and the impediments of article 6, as well as the ranking of applicants, are decided by the landlord entity and do not enter this calculation.

Article 23 gives a right to have the rent revised when the composition or the income of the household changes, and the tenant must tell the landlord within 30 days. A municipality may approve its own regulation, which can never be less favourable than this law.