How to claim an unpaid invoice in your company? Procedures and strategies to manage them

When a customer does not pay an invoice within the agreed term, a situation arises that can generate financial and operational complications for any business. For this reason, knowing how to claim an unpaid invoice effectively and with legal support is essential to ensure collection.

If you want to know how to claim invoices in your company, we invite you to take note of the steps to follow before formalizing a claim, the available procedures and strategies to avoid future non-payments.

If you stay with us, here’s what you can find out in this article:

• Steps prior to claiming an invoice: importance of having the documentation in order and communicating amicably with the customer.
• Formal claim of the unpaid invoice: how and when to send a certified letter to demand payment of the invoice, and out-of-court alternatives.
• Possible legal actions: what are the legal options available, such as the payment order procedure or the judicial route to claim debts.
• How to prevent non-payment of your company’s invoices: proactive measures to avoid future non-payments.

Your company has been waiting for a long time for the payment of that invoice and it is still not paid. What now? Before initiating a formal claim, it is advisable to exhaust all amicable ways to solve the problem.

Read on to discover the initial steps to protect your business!

The first step is to make sure that all documents are in order. To do this, you will need to verify certain aspects:

• The invoice has been correctly issued, with all the fiscal data of your company and details of the service or product provided.
• It has been sent to the customer and there is proof of receipt.
• The terms of payment and maturity have been clearly specified.
• There are no errors in the amounts or description of services.

Having this documentation will facilitate the claim process and avoid possible allegations by the customer.

After verifying that all documentation is in order, the next step is to contact the client to remind him/her of the existence of the debt, understand the situation and clarify the solution.

To do this, your company can use different means of communication. One is the telephone call, a quick and direct option.

You can also choose to send a WhatsApp or an email, which, being written means, allow you to record your complaint. In addition, if you use certified e-mail services o WhatsApp certified for companies, such as those offered by MailComms Group, you will have a legally valid proof in case of future actions.

Regardless of the means you choose, if the customer does not respond or refuses to pay, it will be necessary to move on to a formal claim. Here’s how to claim an unpaid invoice with a more regulatory procedure.

In the event of non-response or continued non-payment by the customer, it is necessary to initiate a more structured procedure to demand payment of the invoices.

If you are wondering how to claim invoices in a formal way, you should start with a letter of claim to formalize the demand for payment. This should include:

• Your company and debtor’s data.
• The number and date of the unpaid invoice.
• The amount owed.
• A deadline for payment before taking further legal action.

To guarantee the legal validity of the claim, it is recommended that it be a registered letter, although it is best if it is a burofax, since this, in addition to corroborating the receipt of the document, also certifies the content of the message.

→ Not all certified shipments are the same. Discover the difference between a bureaufax and a certified letter and which is the best option for each situation.

In addition, today there are options such as the online burofax for companies, with the same legal validity, but with greater convenience and speed, allowing companies to optimize their workflow.

In many cases, negotiating with the debtor may be the best option to obtain payment without resorting to legal action. In these cases, alternatives such as payment deferrals or instalments, or written agreements acknowledging the debt and establishing a new payment schedule may be considered.

For example, a company may negotiate with its supplier an instalment payment plan to settle the outstanding debt and thus preserve a sound business relationship.

If direct negotiation does not produce results, a mediation or conciliation service may be used . This process involves the intervention of an impartial third party who helps both parties to reach an agreement without the need to go to court, reducing costs and time.

There are also collection agencies, which collect the debt for you in exchange for a commission.

Mediation services to reclaim unpaid invoices can be an effective solution in sectors where reputation is key, such as finance.

Now, if none of this has worked, here are the legal actions available.

On April 3, Law 1/2025 on measures for the efficiency of the Public Justice Service, also known as the Mediation Law, will enter into force, establishing Appropriate Means of Dispute Resolution in non-jurisdictional channels (ADR) and the obligation to resort to them in certain cases before filing a lawsuit, such as in the case of a claim for non-payment of an invoice, through the intervention of a third party (collection entities), such as a mediator, conciliator or entity assigned for such purpose, or, on an individual basis, the parties may reach an agreement.

That is to say, a requirement of admissibility of the claim is to have tried to reach an agreement with the opposing party, in this case, the debtor, before going to court, and also to be able to demonstrate with documents that this agreement has been attempted.

If out-of-court procedures do not work, the legal route is the next step that answers how to claim invoices. Depending on the amount and circumstances, different options may be given:

• Payment order procedure. It is a quick and simple judicial procedure, protected by the Civil Procedure Law, to claim documented economic debts.
• Verbal trial or ordinary trial. If the debtor opposes the order for payment, it will be necessary to go to an oral or ordinary trial depending on the amount owed.

At this point you may be wondering: can I prevent non-payment of invoices in my company? The answer is yes, read on!

Even if you already know how to claim an unpaid invoice, the ideal is to reduce the risks of non-payment in the future. To do this, you can:

• Verify the customer’s creditworthiness before offering credit.
• Establish clear payment terms and have them signed before providing the service.
• Automate payment reminders to avoid unintentional delays.
• Requiring advance payments or guarantees on large contracts.

Taking these measures will significantly reduce the problems of unpaid invoices in your business. If, in addition to this, you contract MailComms Group’ s electronic invoicing service, you will be guaranteed traceability, security and document retention, among many other benefits.

Want to know more about it? We answer all your questions!

If an invoice is not paid, the first thing to do is to contact the customer to remind them of the payment. If they do not respond, a formal complaint should be sent and, ultimately, legal proceedings should be initiated.

The term to claim an invoice varies according to the legislation of each country and the nature of the debtor, but in Spain, in general, it ranges between 3 and 5 years from the due date of the invoice.

If you do not have proof of shipment, it will be difficult to claim it. Therefore, it is advisable to count on the legal validity of certified e-mail or other certified or other certified communications in your company to guarantee that the invoice has been delivered.

Not always. The first step is to claim the invoice in a friendly manner, for example in the case of claims against insurance companies, so no lawyer is necessary. In the case of an order for payment procedure, it can also be initiated without a lawyer if the debt is less than 2,000 euros, although it is always advisable to have legal counsel in more complex cases. For other legal proceedings, it will be necessary to have this professional.

If the customer does not respond and cannot be located, it is possible to start a search procedure or, ultimately, to claim the debt through legal proceedings.

There is no mandatory deadline for sending it, but it is recommended to send it as soon as the non-payment is detected, in order to avoid the statute of limitations of the debt. For this purpose, it is advisable to fill out a burofax model for claims.