When old debts expire in Portugal (prescrição)

In short: In Portugal, a debt does not last forever — but how long it lasts depends completely on what kind of debt it is. A signed contract debt runs for the ordinary 20 years (Código Civil art. 309), rent and interest for 5 years (art. 310), most invoices from professionals and shops for 2 years (art. 317), and everyday utility bills for just 6 months (art. 10 of Lei 23/96). And the clock can be reset to zero by a court action — or by your own partial payment. CourtStairs answers questions like these in plain language, with citations to the Diário da República you can open and check yourself.

If a creditor is chasing an old bill, the first question is not "how much" but "how old, and of what type." Portuguese law calls the expiry of a claim prescrição (prescription, or limitation). This post gives you a table of the main periods by debt type, explains when the clock starts, and — most importantly — shows exactly which acts interrupt it and start a fresh period. Plain English, for expats, foreigners and Portuguese readers who search in English.

First, what "prescrição" actually does

Prescription does not erase the debt or delete the creditor’s right. It gives you a defence: once the period has run, you can lawfully refuse to pay (art. 304 of the Código Civil). Two consequences catch people out.

• You must raise it yourself. A court never applies prescription on its own initiative — the person who benefits from it has to invoke it (art. 303). Ignore a lawsuit and you can lose even on a debt that expired years ago.
• Pay it and you cannot claw it back. If you pay a prescribed debt without knowing, art. 304 says you cannot demand the money back. The right still "existed"; prescription only lets you decline to honour it.

The periods by debt type

Here is the practical map. Match your debt to a row, then note the period and the article — because the difference between 20 years and 6 months is enormous.

A word on the "consumer" debts people worry about most. There is no special 5-to-6-year rule for ordinary consumer purchases in Portuguese law — most shop and professional invoices fall under the 2-year presumptive period of art. 317. The 5-year figure is for recurring payments (rent, interest, instalments) under art. 310. And your monthly electricity, water and phone bills are the fastest of all: 6 months under the Lei dos Serviços Públicos Essenciais.

When does the clock start?

The general rule is art. 306: prescription starts to run when the right can first be exercised — normally the day the debt falls due, not the day the contract was signed or the goods were delivered. Two refinements come up often:

• If the debtor only has to pay a set time after being notified, the clock starts once that time has passed.
• For a debt under a suspensive condition or an initial term, it starts when the condition is met or the term arrives.

Getting this date right is half the battle, because every deadline above is counted from it.

What interrupts the clock — and starts a fresh period

This is where old debts come back to life. Portuguese law separates two things that sound similar but are not:

Interruption is the powerful one, and there are two everyday triggers:

• A court summons or judicial notification of the claim (art. 323). The moment the debtor is summoned — or notified of any act showing the creditor’s intention to enforce the right — the clock resets, whatever the type of proceeding and even if the court turns out to be the wrong one. There is a safeguard for creditors: if the summons is not served within five days of being requested, for reasons not down to the claimant, prescription counts as interrupted once those five days pass.
• Your own acknowledgement of the debt (art. 325). If the person who owes the debt recognises it — by making a partial payment, signing a payment plan, or promising in writing to pay — that recognition interrupts prescription and a fresh full period starts. This is the trap: a €20 goodwill payment on a nearly-expired invoice can hand the creditor years more to chase the balance.

1. Debt falls dueThe clock starts when the right can first be exercised (art. 306).
2. Time runsThe applicable period elapses: 20 years, 5 years, 2 years, or 6 months.
3. Interruption (if it happens)A court summons (art. 323) or your acknowledgement (art. 325) resets the clock to zero — a new full period begins.
4. Period completesYou can invoke prescription and lawfully refuse to pay (arts. 303–304).

Creditor or debtor: what to do

If you are owed money, do not let a short period lapse while you negotiate. Informal reminders, emails and WhatsApp messages do not stop the clock — only a formal court step under art. 323 does. For a 2-year invoice or a 6-month utility debt, that window closes fast.

If you are being chased, identify the debt type and its start date, then check whether the period has already run. If it has, you can invoke prescription — ideally in writing — and decline to pay. But watch the interruption traps above, and remember that special regimes (tax, labour, road-traffic) run on their own timetables outside the Civil Code. For a broader map of Portuguese deadlines, see our guide to prescription periods and legal deadlines in Portugal. If a creditor does sue, small-value disputes often go through the informal Julgados de Paz small-claims courts.

Where CourtStairs fits

This is exactly the kind of question CourtStairs is built for: it separates the debt type, matches it to the right period, and links each point to its source — art. 309 for contracts, 310 for rent and interest, 316–317 for invoices, art. 10 of Lei 23/96 for utility bills, 323 and 325 for what resets the clock — so you can open the Diário da República and read the provision yourself. It works in English and Portuguese and has a free tier.

This is general information about the law, not legal advice. Prescription turns on the exact type of debt, its start date, and whether the clock was ever interrupted; special regimes abound and the law changes, so confirm anything important against the primary source or a qualified lawyer before you act.