Invoicing requirements for SMEs and self-employed workers
Guide to mandatory details, complete, simplified, and corrective invoices, numbering, VeriFactu, and invoice management in Spain.
Updated 3 September 2026
An invoice documents a supply of goods or services. In Spain, its contents and retention are subject to the invoicing regulation and VAT rules.
This guide summarizes the concepts that often affect SMEs and self-employed workers. To issue documents from Numonis, use the step-by-step Sales Invoices guides.
What a complete invoice contains
As a general rule, a complete invoice includes:
- A sequential number and, where relevant, series.
- Issue date and transaction date when different.
- Name or registered business name and tax number of the issuer and recipient.
- Address of the issuer and recipient.
- A sufficient description of the goods or services.
- Taxable base, VAT rate, and VAT amount shown separately.
- Total amount.
- Special wording required for exempt transactions, reverse charge, special regimes, or other cases.
An invoice may need more information because of the transaction, recipient, or tax regime. Review the details before issue and then use a correction flow that preserves the audit trail.
Complete and simplified invoices
A simplified invoice contains fewer details and may only be used in permitted cases. Spain's Tax Agency identifies cases including:
- Transactions up to EUR 400, including VAT.
- Corrective invoices.
- Certain activities up to EUR 3,000, including VAT, such as retail sales, hospitality, or passenger transport.
If a business or professional needs to deduct VAT from a simplified invoice, it must also show their tax number and address and the VAT amount separately. Do not use a simplified invoice only because it is quicker.
Numbering and series
Numbers within each series must be sequential. Separate series can be used when there is an operational reason or specific requirement, for example for certain establishments or corrective invoices.
Avoid deleting issued numbers or reusing them. If an issued invoice contains an error that affects its tax details or amounts, use the edit or correction flow available for its status and preserve the audit trail.
Corrective invoices
A corrective invoice corrects an earlier invoice when requirements were not met, VAT was calculated incorrectly, taxable bases changed, or another accepted reason occurred. It must identify the corrected invoice and describe the correction.
The process depends on the error and status of the transaction. Ask your adviser before replacing, cancelling, or correcting an issued invoice.
Electronic invoicing and VeriFactu are not the same
- Electronic invoicing describes an invoice issued and received electronically. Some contexts require a specific format or channel, such as Facturae.
- VeriFactu is one compliance mode under the rules that apply to computerized invoicing systems and their records.
An invoice can be electronic without that fact alone satisfying every VeriFactu rule. Read the VeriFactu and certified invoicing guide to understand the difference.
Before issuing an invoice
- Confirm the issuer's and customer's tax details.
- Select the correct document type and series.
- Clearly describe the goods or services.
- Review taxable bases, VAT rates, withholding, and totals.
- Check any special wording required for the transaction.
- Review the preview and issue only when the details are final.
The invoice VAT and withholding calculator can help you estimate amounts. The correct rate or withholding depends on the transaction and your circumstances.
How Numonis helps
Configure your details, series, taxes, and payment methods before issuing. You can then create an invoice, review its status, send it, and mark payment from the platform.
Frequently asked questions
Can I change an invoice after issuing it?
It depends on its status. Numonis may allow direct editing of an issued or sent invoice that is not certified or paid and has no corrective invoice. Certified, paid, processing, or already corrected invoices require a corrective invoice or guidance from Numonis. See the invoice lifecycle.
Is a quote or proforma an invoice?
No. They present a proposal or preliminary information, but they do not replace the invoice that documents the transaction.
Must I retain invoices?
Yes. Both issuer and recipient must retain invoices and supporting documents for the applicable periods. The period can differ according to the tax, commercial requirement, or transaction type.
Official sources
Notice
This content is informational and describes general rules. It does not replace personalized tax advice.
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