Errors in the return
How to correct a mistake in your return: amending and complementary documents
In the event of an error in the declaration, there are several possibilities depending on the type of error:
If you have paid more or have declared a lower amount of VAT to be compensated or returned , you can request rectification of the self-assessment presented before four years have passed since the deadline for submitting the aforementioned self-assessment ended.
If you have paid less or have declared a greater amount of VAT to compensate or return , you must submit a complementary self-assessment , checking the "complementary self-assessment" box of form 303, indicate the receipt number of the previous self-assessment and fill in the "To be deducted (exclusively in case of complementary declaration)" box with the amount of the result of the previous self-assessment. In the complementary that correspond to self-assessments submitted from 2023 onwards, the box “To be deducted (exclusively in the case of complementary declaration)” disappears and is replaced by: box 70 for income made or box 109 for returns obtained.
If you have requested compensation and wanted a refund, or vice versa, you can request rectification of the self-assessment submitted if the deadline for submitting the return has not expired.
If the error refers to an information box or the account number in which the refund is requested, or another error that does not affect the result of the settlement , you must submit a request for rectification of the self-assessment before four years have passed since the deadline for submitting the aforementioned self-assessment expired.