The first invoice and the registration date
The invoice has to fall on a day covered by the census and by RETA. The app’s numbering does not ask the Tax Agency whether you were registered that day.
The date has to be covered
Do not put on the invoice a day before the census registration and RETA cover you. The census registration is filed before the activity starts. If the work belongs to a day when you were not yet registered, that date does not fit.
- The census and RETA have to cover that day.
- Census registration comes before the start.
- An earlier date leaves the invoice outside that cover.
Numbering does not check registration
If you create the invoice, Factura Fácil assigns a number. That does not look up your census or your enrolment. How the invoice is built is in how an autónomo invoice works.
Common questions
Can I date the invoice the day before I register?
No. The date has to be covered by the census and by RETA. The census registration is filed before you start.
If the app numbers the invoice, am I registered?
No. The number is assigned when you create the invoice. It is not a check with the Tax Agency or Social Security.
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.