Compliant with DL 62/2013

Late-payment interest calculator

Calculate the late-payment interest you are entitled to charge customers in arrears. ECB rate + 8% per year, applied automatically on B2B transactions, under Portuguese law.

Calculate the late-payment interest due

Enter the invoice details and the due and payment dates to calculate the applicable statutory interest.

Days overdue
Interest rate (% p.a.)
Interest due (€)

The applicable legislation

In Portugal, late-payment interest on commercial transactions is governed by Decree-Law No. 62/2013, of 10 May, which transposed the European Parliament's Directive 2011/7/EU on combating late payment.

Decree-Law No. 62/2013 — key points

  • B2B (business to business): maximum payment term of 60 days. After that term, automatic late-payment interest.
  • B2G (business to government): maximum term of 30 days. The public sector has stricter rules.
  • Automatic application: interest is due without any need for notice, notification or a judicial demand.
  • Rate: ECB reference rate + 8 percentage points, revised every six months.
Late-payment interest formula Interest = Amount × (ECB rate + 8) / 100 × Days / 365

Example: Invoice 15 000 € | 45 days overdue | ECB rate 2.65%
Interest rate = 2.65% + 8% = 10.65% p.a.
Interest = 15 000 × 0.1065 × (45/365) = 196.92 €

The ECB reference rate is set by Banco de Portugal and published in the Diário da República in January and July each year. In 2026, the rate stands at 2.65%, resulting in a late-payment interest rate of 10.65% per year.

How to charge late-payment interest

Although interest is due automatically by law, you must formalise it in order to collect it. Follow these 3 steps:

Step 1

Issue a debit note

Issue a debit note referencing the original invoice, the days overdue and the amount calculated under DL 62/2013. Include the IBAN for payment.

Step 2

Collection letter

Send the debtor a registered letter with acknowledgement of receipt, stating the payment deadline (e.g. 15 days) and mentioning the possibility of an enforcement action in the event of non-payment.

Step 3

Enforcement action

If the debt persists, engage an enforcement agent. The invoice and the debit note constitute an enforceable title, allowing a simplified procedure without a prior declaratory action.

How to avoid paying late-payment interest

If it is your company that has to pay suppliers, these are the best practices to avoid incurring late-payment interest:

Use confirming

Confirming ensures suppliers are paid within the agreed term, automatically. It removes the risk of default from an oversight or a temporary liquidity gap.

Learn more about confirming →

Negotiate realistic terms

When signing contracts, negotiate payment terms you can comfortably meet, taking your collection cycle (DSO) into account. A DPO higher than your DSO creates treasury pressure.

Calculate DPO →

Set up due-date alerts

Many cases of late payment come down to simply forgetting. Set up automatic alerts 5 and 2 days before supplier invoices fall due so you are never caught by surprise.

Manage it on the Advanta platform →

Payment delays by sector in Portugal

The average payment term in Portugal is 71 days, well above the 60-day legal limit for B2B transactions. The sectors with the highest incidence of late payment:

Public Sector
112 days
actual average term · legal limit 30 days
High default risk
Construction
95 days
actual average term · legal limit 60 days
High default risk
Large Retail
78 days
actual average term · legal limit 60 days
Moderate risk
B2B Services
68 days
actual average term · legal limit 60 days
Moderate risk
Industry
52 days
actual average term · legal limit 60 days
Low risk
Retail
38 days
actual average term · below the limit
No default risk

Source: Banco de Portugal, Intrum European Payment Report 2025. Illustrative data based on sector averages.

Frequently asked questions

Is late-payment interest automatic, or do I need to notify the customer?
Under Decree-Law 62/2013, late-payment interest is due automatically from the day after the due date, with no need for a judicial demand or prior notice. However, to collect it in practice, you must issue a debit note and notify the debtor. The right exists regardless of notification, but collection requires formalisation.
Can I charge late-payment interest if it is not in the contract?
Yes. One of the most important features of DL 62/2013 is that the right to late-payment interest exists whether or not it is provided for in the contract, it is an automatic legal right in all commercial transactions between businesses (B2B) or between businesses and the State (B2G). Contract clauses that exclude or limit this right are void.
What is the applicable late-payment interest rate in 2026?
In 2026, the ECB reference rate is 2.65%, so the commercial late-payment rate is 10.65% per year (ECB 2.65% + 8 percentage points). This rate is revised every six months by Banco de Portugal. For the second half of 2026, the rate published in the Diário da República in July 2026 applies. The applicable rate is the one in force at the moment the delay starts to count.

Never pay late-payment interest again

With Confirming, Advanta ensures your suppliers are paid within the legal term. Your company repays in 60-90 days, with no risk of default.