DSTI at 45%: what changes in mortgage lending in 2026

On 1 August 2026, Banco de Portugal’s revised macroprudential recommendation came into force — and with it, the maths the bank does before saying “yes” to you got tighter. The recommended debt-service ratio (DSTI) limit fell from 50% to 45%, and the margin banks had to grant exceptions shrank. If you’re preparing to buy, this directly affects the maximum amount you can borrow.

What actually changed

Four things, all applicable to loan agreements whose solvency assessment is carried out from 1 August 2026:

Rule	Before	Now
Maximum debt-service ratio (DSTI)	50%	45%
Exceptions per bank	15% of new lending	10%
Maximum term up to age 35	40 years	40 years (unchanged)
Maximum term above age 35	37 years (30–35) / 35	35 years

The financing cap stays the same: 90% of the price for a primary residence, 80% for other purposes — and the exception allowing 100% financing of bank-owned properties has ended.

How the bank does the maths (and why it’s tougher than it looks)

The debt-service ratio adds up all the household’s loan payments — mortgage, car, personal loans, credit cards — and divides by net monthly income. With €2,500 net, the 45% ceiling means a cap of €1,125 for total payments.

But there’s a second squeeze almost nobody counts: the stress test. The bank doesn’t simulate the payment at the rate you sign for — it simulates it with a shock of 1.5 percentage points added on terms above 10 years (0.5 points up to 5 years; 1.0 between 5 and 10). With the 6-month Euribor at 2.723% and a 0.9% spread, the 3.623% TAN is tested at 5.123%. A fixed rate is the exception: it carries no shock at all.

How much you can still borrow: an example

A couple with €2,500 net, no other loans, a 30-year term, variable rate: the maximum test payment of €1,125 at the stressed rate corresponds to around €206,663 of principal. The real payment would come to €942.26 — an effective debt-service ratio of 37.7%.

Two scenarios change this maths dramatically:

• Fixed rate: with no stress shock, the maximum rises to around €246,744 — an extra 40 thousand euros of capacity, just from the structure of the rate.
• Other loans: €300 of existing payments cuts the maximum to around €151,553. Every euro of an old payment is deducted euro for euro from the ceiling — paying off a personal loan before applying for the mortgage is, often, the best investment you can make.

You can run this maths with your own numbers in the debt-service ratio calculator.

A recommendation, not a law — but it comes close

Technically, Banco de Portugal recommends; it doesn’t ban. Each bank can exceed the limit on up to 10% of the new lending it grants, on an exceptional and justified basis. In practice, with the margin shrinking from 15% to 10%, banks will save those exceptions for very strong files — don’t count on them to stretch your budget.

And there’s a third, quiet factor: if the contract would run past your 70th birthday, the bank is advised to simulate your reduced retirement income. A shorter term or an older age can cut the real maximum below what the plain maths suggests.

What to do about it

If your capacity dropped with the new rule, there are four levers, in order of effectiveness: pay off existing loans (euro-for-euro effect on the ceiling), consider a fixed rate (removes the test’s shock), extend the term within your age limit (lowers the test payment), and increase your down payment (less principal requested). The state guarantee scheme is still available to finance the down payment up to age 35 — but be careful: the guarantee solves the down payment, not the debt-service ratio, which still applies all the same.