Double invoice on vAT declaration

The only option I can see is to notify your customer that you have made a mistake in your vAT declaration and that you will therefore send them another invoice for an amount already paid and a credit note for the same amount (which they do not have to pay but simply enter as paid). Then send them the second invoice (with the original date and number) and immediately afterwards a credit note (with a date in the next declaration period (month or quarter depending on your VAT registration) for the same amount. You then submit this credit note to the VAT authorities with your next return. This means that you will have to wait until after the next return has been settled before you can recover the VAT on it.

An alternative is to contact the vAT administration, give an explanation for everything and ask how best to solve this (perhaps you can also enter this in the next return as a correction to the previous return).

Johan