When a Debt in Portugal Expires in 2026: A Practical Guide to Prescrição, the Six Months on a Water Bill, the Two Years on a Traffic Fine, the Eight on Tax, the Twenty That Follow a Judgment, and the Sentence That Restarts the Clock

A letter arrives about an electricity bill from 2019. A collection agency calls about a gym membership you cancelled in 2021. A parking fine surfaces from a car you sold. In every case the first question is the same, and almost nobody asks it correctly: not "do I still owe this?", but "has the time run out, and if it has, what do I have to do about it?"

Portuguese law calls the answer prescrição (prescription, or limitation). It is not a single period. It is at least a dozen periods, ranging from six months to twenty years, sitting in different statutes, starting from different events, and stopped by different things. This guide sets out which one applies to what, what restarts the clock, and the two rules that catch people out most often.

The rule almost everyone gets wrong

Prescrição does not delete a debt. Article 304(1) of the Código Civil (Civil Code) says that once the period is complete the beneficiary acquires the right to refuse to perform, or to oppose the exercise of the right in any way. The obligation itself survives as what lawyers call a natural obligation.

Two consequences follow, and both matter in practice.

First, article 303: a court cannot apply prescrição on its own initiative. It must be invoked, judicially or out of court, by the person it benefits. If you are sued over a debt that expired eleven years ago and you defend on the merits without raising prescrição, you can lose. The judge is not permitted to rescue you.

Second, article 304(2): if you voluntarily pay a prescribed debt, you cannot get the money back, even if you paid in complete ignorance that the period had run. The same applies to recognising the debt or giving a guarantee over it. There is no "I did not know" refund.

Two smaller rules complete the frame. Article 300 makes void any agreement that lengthens, shortens or otherwise alters the legal prescription regime, so a clause in a contract extending the period is worth nothing. Article 302 allows you to waive prescrição only after the period has already run, never in advance, and a waiver can be tacit.

The default: twenty years

Article 309 is one sentence: the ordinary prescription period is twenty years. Everything not given a shorter period elsewhere falls here. A private loan between two people, a claim for the price of a one-off sale between two companies, an unpaid balance on a settlement agreement: twenty years, counted under article 306 from the moment the right could be exercised.

Five years: anything that repeats

Article 310 sets five years for obligations that renew periodically. The list is specific:

• instalments of perpetual or life annuities;
• rents and hire payments owed by a tenant or hirer, even where paid in a single sum;
• foros (ground rents);
• interest, conventional or legal, even when the amount is not yet fixed, and company dividends;
• capital amortisation instalments payable together with interest;
• maintenance payments already fallen due;
• any other periodically renewable payments.

Two of these carry weight for foreign residents. Unpaid rent runs out in five years, not twenty. And interest runs out in five years independently of the capital, which means an old debt can be legally recoverable while most of the interest claimed on it is not.

Six months and two years: the presumption of payment

The Civil Code then does something unusual. Articles 312 to 317 create "presumptive" prescriptions, built not on the idea that the creditor slept on the right but on the presumption that you already paid. These are the everyday consumer periods.

Six months (article 316): credits of establishments providing lodging, food or drink, for the lodging, food or drink they supply. Hotels, restaurants and bars.

Two years (article 317), in three groups:

• establishments providing lodging, or lodging and food, to students, and the credits of teaching, education, assistance or treatment establishments for services rendered. Schools, colleges, care homes and clinics;
• credits of merchants for goods sold to someone who is not a merchant or does not buy for their trade, and credits of those who professionally carry on an industry for supplying goods, carrying out works or managing another's business, including their expenses, unless what was supplied was for the debtor's own industrial activity. In short, most retail and most tradesmen billing a household;
• credits for services rendered in the exercise of the liberal professions, and reimbursement of the corresponding expenses. Lawyers, architects, doctors in private practice, accountants.

Now the trap. Because these periods rest on a presumption of payment, article 313 says the presumption can be rebutted only by a confession from the original debtor or from someone who inherited the debt, and an out-of-court confession only counts if it is in writing. Article 314 adds tacit confession: refusing to testify or to swear in court, or doing anything in the proceedings incompatible with the presumption that you paid.

So the fatal move on a two-year debt is to write "I know I owe this, I just cannot pay right now." That single sentence, in an email or a WhatsApp message, is a written confession. It destroys the presumption, and article 315 then leaves the obligation under the ordinary rules, which is to say twenty years. If the period has run and you want the benefit of it, say that the debt is prescribed. Do not explain, apologise or negotiate first.

Six months on water, power, gas, phone and bins

The single most useful period for a household sits outside the Civil Code, in Lei n.º 23/96 (the Law on Essential Public Services). Article 1 lists what it covers: water supply; electricity; natural gas and piped LPG; electronic communications; postal services; waste-water collection and treatment; municipal solid waste management; and passenger transport.

Article 10 then does four things:

• The right to receive the price prescribes six months after the service was provided. Not six months after the invoice was issued, and not six months after somebody noticed.
• If less was paid than the actual consumption, for any reason including the provider's own error, the right to the difference lapses within six months of that payment. This is the answer to the classic retroactive water-meter correction covering three years.
• A demand for payment must be communicated to the customer in writing at least ten working days before the payment deadline.
• The provider has six months to bring the court action or the injunção, counted from the provision of the service or from the initial payment.

The exception in article 10(5) is high-voltage electricity supply, which is industrial. Article 11 puts the burden of proof on the provider for everything relating to its own compliance, expressly including proof that the article 10 communications were made and when. If they cannot show the notice, they cannot rely on it.

If you are setting up accounts for the first time, our guide to household electricity and gas contracts covers the supply side of the same relationship.

Three years: compensation

Article 498 gives three years for a claim in damages, counted from the date the injured party knew of their right, even if they did not yet know who was responsible or the full extent of the loss. The twenty-year ordinary period still runs in parallel from the harmful event itself, so the three years cannot extend beyond it. The right of recourse between jointly responsible parties is also three years, counted from payment. And if the act is a crime carrying a longer prescription, that longer period applies instead.

Eight years: tax

Article 48 of the Lei Geral Tributária (General Tax Law) sets eight years for tax debts. The counting differs by tax:

• Periodic taxes (IRS, IRC, IMI): from the end of the year in which the taxable event happened.
• Single-obligation taxes (IMT, stamp duty): from the date of the event.
• VAT and income taxes withheld at source definitively: from the start of the civil year following, respectively, the date the tax became due or the taxable event.

Where the assessment right falls under article 45(7), covering income routed through low-tax jurisdictions, the period stretches to fifteen years.

Article 49 lists what stops it. Citation in a tax enforcement, a reclamação, a hierarchical appeal, an impugnação and a request for ex officio review of the assessment all interrupt, but the interruption happens only once, with whichever comes first. Suspension is separate and broader: an authorised instalment plan suspends the clock, as does a pending challenge that suspends collection, and so does a criminal investigation until it is closed or the sentence becomes final. This is why an old tax debt that you put on a payment plan and then abandoned may be much younger, in legal terms, than the calendar suggests. If you need to know where you stand, our guide to obtaining a certidão de não dívida explains how to see what the state still records against you.

Five years: Social Security

Article 187 of the Código dos Regimes Contributivos (Contributory Regimes Code) gives five years for contributions, quotas, late-payment interest and other amounts owed to Segurança Social, counted from the date the obligation should have been met. It is interrupted by any administrative step brought to the debtor's knowledge that is aimed at liquidating or collecting the debt, and by a claim. That is a lower bar than the tax rule: a letter that reaches you can be enough.

Two years: traffic fines

Article 188 of the Código da Estrada (Highway Code) says the proceedings for a road traffic contraordenação are extinguished by prescription two years after the offence was committed. Article 189 gives the coima itself, and any accessory sanction such as a driving ban, two years from the moment the condemnatory decision becomes definitive or the judgment becomes final.

Two qualifications matter. Article 188(2) makes notification of the condemnatory decision an additional interrupting event, on top of the general regime. And that general regime, the Regime Geral das Contraordenações (General Regime of Administrative Offences, Decreto-Lei n.º 433/82), contains in its article 28(3) a hard outer limit: proceedings always prescribe once the normal period plus half has elapsed, leaving aside time when the clock was suspended. For a road offence that is three years of running time, plus suspensions capped at six months in the two most common cases under article 27-A. Our guide to paying and contesting a traffic fine covers the notification and payment stages that precede all of this.

One, three or five years: every other fine

For non-traffic administrative offences the RGCO sets the period by reference to the maximum fine the offence carries, not the fine actually imposed. Under article 27, proceedings prescribe in five years where the maximum coima is 49,879.79 euros or more; three years where it is at least 2,493.99 euros and below that ceiling; and one year in all other cases.

Once a fine has been imposed and the decision is definitive, article 29 gives it three years to prescribe if it exceeds the general maximum in article 17(1), and one year otherwise. For individuals that general maximum is 3,740.98 euros for a deliberate offence and 1,870.49 for a negligent one; for companies it is 44,891.81 and 22,445.91. In plain terms, most ordinary municipal and regulatory fines against a private individual prescribe one year after the decision becomes definitive, unless enforcement or an instalment arrangement suspends the clock under article 30.

What stops the clock

Portuguese law separates two mechanisms, and the difference is large.

Suspension pauses the clock and then resumes it. Articles 318 to 322 cover the cases: between spouses, between a guardian and the person under guardianship, between a company and its directors in respect of their conduct in office, while a domestic worker's contract lasts, and, under article 320, in favour of minors and of adults under an accompaniment order. Article 321 adds force majeure, but only if it strikes in the last three months of the period.

Interruption destroys everything that has run. Article 326 is explicit: the time elapsed is wiped out and a new period begins. There are two ways it happens.

Article 323: citation or judicial notification of any act that expresses, directly or indirectly, the intention to exercise the right, whatever process it belongs to and even if the court has no jurisdiction. If the citation is not served within five days of being requested for reasons outside the applicant's control, the prescription counts as interrupted once those five days pass. Article 327 then holds the new period frozen until the decision ending the proceedings becomes final, which is why a debt tied up in a long court case does not quietly expire during it.

Article 325: acknowledgement of the right, made to the holder by the person against whom it can be exercised. Tacit acknowledgement counts only where the facts unequivocally express it, which in practice means a part payment, a signed payment plan, or a written admission.

This is the mechanism behind the collection-agency phone call. The purpose of the call is very often not to collect. It is to obtain an acknowledgement, because an acknowledgement restarts a clock that may be nearly out.

The rule that converts short periods into long ones

Article 311 is the one to remember if you have ever been taken to court. Where the law sets a shorter period than the ordinary one, including a presumptive period, the right becomes subject to the twenty-year period once a final judgment or another executive title recognises it. A two-year invoice, once it goes through an uncontested injunção and acquires an enforcement title, becomes a twenty-year debt. The exception in article 311(2) is that payments not yet due when the judgment was given keep their short period.

That is why ignoring an injunção is so much worse than defending it badly, and why an old enforcement can still reach your salary or your bank account long after the original bill would have expired.

Prescrição is not caducidade

The Civil Code's third section, articles 328 to 333, deals with caducidade (lapse), and confusing the two costs cases.

Caducidade is a deadline to act. It does not suspend or interrupt except where the law says so (article 328), and it starts when the right can legally be exercised (article 329). Critically, article 333 says the court assesses caducidade of its own motion, and it can be raised at any stage of the proceedings, where it concerns matters outside the parties' disposition. Where the matter is within their disposition, it follows the article 303 rule and must be invoked.

The practical markers: prescrição gives you a defence you must raise; caducidade kills the right itself, and a court will notice. Deadlines to challenge a dismissal, to contest a company resolution, to exercise a right of first refusal, or the six-month lapse rule for underbilling in article 10(2) of Lei 23/96, are all caducidade.

What this means for you

• If a collector contacts you about an old consumer debt: work out the period first, from the date the service was provided or the goods delivered, not from the date of the last letter. Then reply once, in writing, saying only that you consider the debt prescribed and inviting them to stop contacting you. Do not offer a partial payment, do not ask for a discount, and do not say you cannot afford it.
• If you are sued: raise prescrição in the defence. The court will not do it for you, and it is not something you can add later once judgment has gone against you.
• If you are the creditor: the six-month periods in Lei 23/96 and article 316 run fast, and article 10(4) gives you the same six months to actually file. Sending reminders does not interrupt anything. Only citation, judicial notification or an acknowledgement from the debtor does.
• If you are a landlord: unpaid rent has five years, but the moment you obtain a judgment or an enforcement title the arrears become a twenty-year claim under article 311.
• If you have moved to Portugal recently: a debt from abroad does not gain Portuguese periods by your moving. Which law governs it is a separate question, usually settled by the contract or by EU private-international-law rules, and it should be checked before you rely on any period at all.
• If the sums are small: disputes up to 15,000 euros can be taken to the julgados de paz, where you do not need a lawyer; and if cost is the obstacle, apoio judiciário covers court fees and a lawyer for those who qualify.

None of this is a reason to stop paying bills. It is a reason to check a date before you answer a letter about one. The periods are in the statutes, they are public, and the single most expensive thing you can do with an expired debt is to acknowledge it in writing before you have looked.

This guide describes the law in force in Portugal in September 2026 and is general information, not legal advice on your situation. Prescription periods turn on precise dates and on what interrupted them; if a specific debt matters to you, have the dates checked.