Customer has not paid an invoice: what to do in Portugal

What to do now: verify, contact and put it in writing

If a business customer has not paid by the agreed date, confirm the debt today, speak to the person responsible and send a written payment request with a clear deadline. Do not leave the account in an informal follow-up loop and do not start with threats you are not prepared to act on.

Use this order:

1. confirm the due date, amount, VAT, delivery and payment details;
2. check for a complaint, credit note or administrative error;
3. contact the customer and identify the payment decision-maker;
4. send a written reminder with a specific new date;
5. record every contact, document, promise and missed commitment.

This separates a fixable error from a default that needs formal action. It also preserves the commercial relationship while keeping evidence and options available to the creditor.

Choose the next step according to the cause

• Administrative error: correct the document and confirm receipt.
• Dispute: request it in writing and separate disputed and recognised amounts.
• Payment promise: confirm a concrete date by email.
• Cash difficulty: stop further exposure and assess a written plan.
• Silence or missed promise: prepare a formal notice and escalation.

1. Confirm that the invoice is actually overdue

Review the order or contract, invoice, proof of delivery, agreed term and payment details. Check that the customer received the document and that your business met any conditions required before invoicing.

Look for four common causes: the invoice went to the wrong contact, a purchase-order number is missing, the goods or service are disputed, or payment has been made but not reconciled. Resolving an administrative problem promptly prevents it becoming a commercial dispute.

2. Contact the customer without delay

Make a courteous first contact on the day after the due date, or as soon as the delay is detected. Ask whether anything is preventing payment, confirm who manages accounts payable and request a payment date. Identify the invoice, amount, due date and payment method.

If the customer raises a dispute, ask for it in writing and distinguish the disputed amount from any amount they recognise. If they promise to pay, record the date and email a confirmation of the agreement.

3. Send a complete written reminder

The recipient should be able to understand and verify the request immediately. Include:

• both businesses' legal details;
• invoice number, amount and due date;
• the contract, order or delivery reference;
• the balance still outstanding;
• payment instructions and requested deadline;
• a contact for genuine discrepancies.

Avoid vague wording such as “as soon as possible”. State a date that is reasonable in context and consistent with the next step you are prepared to take.

4. Formalise the notice if silence continues

If the customer does not respond, misses the promised date or disputes the debt without a clear basis, formalise the request. A registered letter with proof of delivery, supported by email, can help evidence what was sent, when and to whom. CTT describes its proof-of-delivery options, including acknowledgement of receipt.

Keep the notice factual. Assemble the invoice, contract or order, proof of delivery, account statement and earlier communications. Do not include allegations you cannot evidence or announce measures that do not fit the agreement or the law.

5. Assess interest, costs and legal escalation carefully

Portugal's Decree-Law 62/2013 provides rules for late payment in commercial transactions, including default interest and, when the legal conditions are met, a minimum EUR 40 contribution to recovery costs. Its scope, exclusions and detailed rules matter, so confirm that it applies before calculating or demanding an amount.

If amicable collection fails, obtain legal advice on the evidence, limitation period, enforceable title and suitable procedure. An order-for-payment procedure may be relevant to some monetary obligations, but an objection by the debtor changes the route. Portugal's Justice portal provides access to order-for-payment case documents and explains when an enforcement formula may be applied.

No letter, platform registration or procedure guarantees recovery. The purpose is to choose a proportionate next step supported by coherent documents.

How Check NicePayer organises this stage

Check NicePayer allows a creditor to assemble the case, validate supporting documents and register a business default in Portugal. The process can track notifications by registered CTT letter and email, retain a traceable history and follow regularisation. Where applicable and after validation, a SIBS payment reference may be provided.

Check NicePayer is a Portugal-only service. Registration does not turn a disputed amount into an admitted debt, replace legal advice or guarantee collection.

If the customer proposes instalments

Record the recognised amount, instalment dates and values, payment method, treatment of interest or costs, consequence of a missed instalment and responsible contacts. Update the balance after every payment.

What not to do

• continue increasing exposure without fresh approval;
• discuss the debt only by telephone;
• publish allegations or personal data through unsuitable channels;
• use threats, impossible deadlines or unsupported amounts;
• wait months before securing proof of delivery;
• confuse persistence with a guarantee of recovery.

Before another sale, read how to check company debts and risk signals in Portugal.

Frequently asked questions

Can default interest be charged on an unpaid B2B invoice?

For commercial transactions within Decree-Law 62/2013, interest may run from the day after the contractual due date. Confirm scope, relevant date and current rate.

Is a registered letter mandatory?

Not in every case for late payment to exist, but delivery evidence helps show when, to whom and on what terms payment was requested.

How much extra time should the customer receive?

There is no universal period. Give a specific, reasonable date consistent with the amount, history and next action.

Is the invoice enough to prove the debt?

Not always. Retain the contract or order, delivery or acceptance evidence, account statement and communications.

When might an order for payment be appropriate?

When a documented contractual monetary obligation remains unpaid. Debtor opposition changes the route, so verify evidence and suitability with legal support.

What if only part of the invoice is disputed?

Request written details, identify the disputed amount and confirm the recognised balance. Keep both parts visible.

Final answer

When a customer does not pay in Portugal, act early: verify the facts, request payment in writing, set a date, document the response and stop new exposure. If delay continues, formalise and choose a plan, registration or legal route based on evidence.