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Calculadora Capital

Supported Rent

In Portuguese social housing the rent comes from the household income, not the market. Enter the two figures from your tax assessment.

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.

Monthly rent
€131.36
Rent over the year (12 months)
€1,576.32
Annual net income€14,700.00
Net monthly income (RML)€1,225.00
Deduction for dependants€134.28
Per-capita factor (12 %)€64.46
Total deductions€198.74
Corrected monthly income (RMC)€1,026.26
Effort rate0.128
Rent as a share of the RMC12.8 %
Minimum rent (1 % of the IAS)€5.37
Maximum rent (conditioned rent)€251.25

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.

The income that counts is net, and that changed in 2016

Article 3(f) defines net monthly income as one twelfth of the sum of the annual net incomes of all members of the household, and paragraph 2 of the same article says exactly where the figures come from: the rendimento global and the coleta líquida as they appear on the personal income tax return validated by the Portuguese tax authority for the previous year. That is why this calculator asks for two fields rather than one: the rendimento global, which is box 1 of the assessment note, and the coleta líquida, which is box 22 of that same note. The difference between them, divided by twelve, is the starting point. The original 2014 wording used GROSS monthly income, and it was Law 32/2016 that moved the calculation to net, with effect from 1 September 2016. That means any guide written before that date computes the rent from the wrong number entirely, and plenty are still online.

The seven deductions stack, and the per-capita factor is separate

Article 3(g) requires seven amounts to be deducted from the net monthly income, all expressed as a percentage of the social support index: 10 % for the first dependant, 15 % for the second, 20 % for each dependant beyond the second, 10 % for each disabled member, which is added to the previous ones if that person is also a dependant, 10 % for each member of the household aged 65 or over, 20 % for a single-parent family and, finally, the amount produced by applying the per-capita factor of Annex I. Two things usually go wrong here. The first is that the first three items accumulate: three dependants deduct 10 % plus 15 % plus 20 %, that is 45 % of the IAS, which in 2026 is 241.71 €, and not the 20 % of the last item applied on its own. The second is that the per-capita factor is not an alternative to the per-person items, it is an additional one that depends only on how many people are in the household: 0 % with one, 5 % with two, 9 % with three, 12 % with four, 14 % with five and 15 % with six or more. A household of five with three dependants deducts both, 45 % plus 14 %. Note too that the 65-and-over item was 5 % in the 2014 wording and Law 32/2016 doubled it to 10 %, so any page predating September 2016 understates the deduction of every household with a pensioner.

The effort rate rises with income, until it stops at 23 %

Article 21 does not set a percentage: it sets a formula. The rent is determined by applying an effort rate to the corrected monthly income, the effort rate being the value, rounded to the thousandth, that results from T = 0.067 × (RMC/IAS). Because the rate itself depends on the corrected income and is then multiplied by it, the rent grows with the square of income rather than in proportion to it: a household that doubles its corrected income sees the rent more than double. That design is what makes social housing weigh very little on those who have very little. The brake is article 21-A, added by Law 32/2016, which says the maximum effort rate may not exceed 23 % of the tenant household corrected monthly income. Working backwards, the rate reaches that 23 % when the corrected income reaches about 1,843.88 €, and from there it grows in a straight line again. The calculator flags when that cap is being applied, because that is the point at which the sum stops being progressive.

The 5.37 € floor and the ceiling that depends on the property value

Article 22 closes the sum from both sides. Paragraph 1 says the rent under the supported-rent regime may not be lower than 1 % of the social support index in force at any given moment, which in 2026 is 5.37 € a month. It is an unconditional floor: a household whose deductions exceed its income pays that 5.37 € and not zero. Paragraph 2 sends the upper limit outside this law: the maximum rent under the supported-rent regime is the maximum rent applicable to residential tenancies under the conditioned-rent regime. That limit has two pieces and each has its own source. Article 3(1) of Law 80/2014 says the rent may not exceed one twelfth of the product of the conditioned-rent rate and the property tax value of the dwelling, and article 1 of Portaria 236/2015 of 10 August fixes that rate at 6.7 %. So the maximum rent is the property tax value times 6.7 % divided by twelve, which is why this calculator asks for it. Worth knowing: paragraph 3 of article 22, which let the landlord apply a higher ceiling corresponding to an effort rate of up to 25 %, was repealed by Law 32/2016, so today the conditioned-rent ceiling is the only one.

Worked example

A couple with two children in a municipal home whose property tax value is 45,000 €. Last year tax assessment shows a rendimento global of 15,000 € and a coleta líquida of 300 €, so the annual net income is 14,700 € and the net monthly income 1,225.00 €. The deductions are 25 % of the IAS for the two dependants, that is 134.28 €, plus 12 % for the per-capita factor of a four-person household, that is 64.46 €, adding up to 198.74 €. The corrected monthly income is therefore 1,026.26 €. The effort rate is 0.067 × (1,026.26 ÷ 537.13) = 0.128, and the rent is 1,026.26 € × 0.128 = 131.36 € a month, or 1,576.32 € a year, which is 12.8 % of the corrected income. It sits above the 5.37 € floor and well below the 251.25 € ceiling the property value allows. Had the same couple a third child, the deductions would rise to 316.91 € and the rent would FALL to 102.61 €.

Frequently asked questions

How is supported rent calculated in Portugal?
The rent is an effort rate applied to the household corrected monthly income. First the net monthly income is worked out, which is the rendimento global minus the coleta líquida from last year tax assessment, divided by twelve. Then the seven items of article 3(g) are deducted, all percentages of the IAS, giving the corrected monthly income. The effort rate is 0.067 times the corrected income divided by the IAS, rounded to the thousandth, and the rent is the product of the two. Finally the 1 % IAS floor and the conditioned-rent ceiling are applied.
What documents do I need to work out my supported rent?
Only last year tax assessment and the composition of your household. From the assessment you take two figures the law itself identifies in article 3(2): the rendimento global, which is box 1, and the coleta líquida, which is box 22 of the assessment table. The property tax value of the home is on the caderneta predial and is only used for the ceiling. Nothing else is needed, because the law requires the figures validated by the tax authority rather than loose income statements.
Do more children raise or lower the supported rent?
They lower it, and by two routes at once. Each dependant adds a deduction to income (10 % of the IAS for the first, 15 % for the second, 20 % for each one after) and, because the household grows, the Annex I per-capita factor rises too. Since the effort rate depends on the already-corrected income, lowering that income lowers both the rate and the base, so the rent falls by more than the deduction alone would suggest.
What is the minimum rent in Portuguese social housing?
One per cent of the social support index, which is 5.37 € a month in 2026. Article 22(1) of Law 81/2014 sets that floor with no conditions at all, so a household whose deductions exceed its income does not pay zero: it pays that minimum. The floor tracks the IAS, so it changes whenever the index is updated.
Is there a maximum supported rent?
There is. Article 22(2) points to the maximum rent of the conditioned-rent regime, which Law 80/2014 defines as one twelfth of the product of the conditioned-rent rate and the property tax value of the home. That rate is fixed at 6.7 % by Portaria 236/2015 of 10 August, so the ceiling is the property tax value times 6.7 % divided by twelve. On a home with a value of 45,000 € the ceiling is 251.25 € a month, whatever the household earns.
Does the supported rent change when my income changes?
Yes. Besides the annual update, 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 thirty days of the event. A revision is also available when a disability of 60 % or more arises, or when a member of the household turns 65, because both create new deductions. The landlord reassesses the circumstances at least every three years.

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Author: Thorben Rasmus Idel · Reviewed by: Nahar Geva · Last reviewed: 2026-09-03