Unpaid invoice reminder letter
Fill in the invoice details and get a polite, clear letter asking for payment, ready to copy or print. You can write it in Spanish or English. It is an indicative template and includes no interest or legal citations.
Sample data
- Amount claimed
- €1,210.00
- Days since the due date
- 15
The letter
Subject: Payment reminder for invoice F2026-0001
Dear Cliente Ejemplo S.L.,
I am writing about invoice F2026-0001, issued on 22 September 2026 for €1,210.00, which fell due on 22 October 2026. As of 6 November 2026, 15 days have passed since the due date and I have no record of payment.
I kindly ask you to pay within 7 days of receiving this letter.
If you have already paid, please send me the proof of payment so I can check it.
If there is any problem with the invoice or you need it sent again, let me know and we will sort it out as soon as possible.
I remain at your disposal. Kind regards,
Estudio Ejemplo
Indicative result: it does not replace an advisor's advice.
Let Collections warn you before you need to chase
Collections tracks what is pending and overdue and reminds you whom to chase.
See Collections Create a free accountHow do I chase an unpaid invoice?
Start with the simplest thing: a friendly written reminder with the invoice details (number, date, amount and due date), a clear deadline and how to pay. Often it is just an oversight. If there is no reply, the same letter works as a formal written claim, and you can keep a copy as proof you sent it.
What should a payment reminder letter include?
Who is claiming and from whom; the invoice (number, date and amount); the date it fell due; what is being asked (payment) and by when; how to pay; and a way to resolve questions. This tool puts it all in a short, courteous text.
What about interest or legal claims?
This letter deliberately includes none. If the customer does not pay after the reminder, ask your advisor how to proceed and what you can claim in your case.
Keep track of what you are owed
This letter handles one invoice. The Collections module flags what is pending and overdue and prepares reminders so no invoice goes unclaimed.
Example
With invoice F2026-0001 for €1,210.00 issued on 22 September and due on 22 October, and the letter dated 6 November, the text says 15 days have passed since the due date and asks for payment within 7 days.
How to use this tool
- Enter your name, the customer's and the invoice details.
- Choose the deadline and the language.
- Copy or print the letter.
Frequently asked questions
When should I send the reminder letter?
When the invoice has fallen due and there is no payment. A friendly reminder a few days after the due date is usually enough.
Does this letter have legal value?
It is an indicative template for claiming in writing. For other legal steps ask your advisor.
Can I write it in Spanish?
Yes: choose the letter language in the form, regardless of the page language.
Do you store my details?
No: the text is generated from what you type and is not saved.
Keep reading
- Invoicing foreign clients from Spain
- How to read a Spanish invoice
- Invoice due date calculator
- Spanish VAT calculator
- VAT and IRPF withholding calculator for invoices
- Free invoice generator
- All free tools
Reviewed on 6 November 2026. Indicative result: it does not replace an advisor's advice.
Get paid on time without chasing invoices by hand
Collections tracks due dates and reminders.
See the module Create a free account