Which activities carry withholding
Withholding on an invoice reaches the professional activities that the income-tax act and its regulation point to. It does not reach every trade. A plumber’s invoice to a company does not carry an automatic 15%. If you are not sure, do not add the withholding.
Professional is not every job
The income-tax regulation lists the kind of income subject to withholding. A business activity in industry or construction does not become professional because the customer is a company. The IAE heading is a guide, but the classification does not come from putting the name of the trade on the invoice. Adding an extra 15% forces your customer to pay a withholding that may not have been due, and forces you to reconcile income that was not that.
- Professions the rule subjects to withholding.
- A business trade does not carry 15% merely for invoicing a company.
- If there is doubt, do not put the withholding on.
The app does not classify the heading
Factura Fácil does not read your IAE heading and does not decide whether your activity is professional. You set the percentage. If you leave it at zero because it does not apply, the invoice comes out without that withholding line.
Common questions
Does a plumber withhold 15% from a company?
Not automatically. Withholding is for professional activities under the income-tax rules. A trade that is not in that group does not carry it merely because you invoice a company.
Does the app look at my IAE?
No. It does not classify your heading. The withholding is the one you enter.
Official sources
Informational text reviewed on 26 September 2026. It is not tax advice and does not replace the Spanish Tax Agency or your accountant. Deadlines, rates, and forms can change.