Identification of the store:
Name and address + ideally identification number (in France: SIRET or SIREN or VAT number; in Belgium: business registration number).
Note: the store stamp can suffice in the absence of printed references on the invoice.
Date.
Invoice number.
Description of each item.
VAT rate for each item (important for stores selling products subject to different VAT rates such as supermarkets, pharmacies, bookstores, FNAC, etc.).
VAT rate and total amount (per VAT rate).
Identification of buyer (name and address of Zapptax).
In Belgium, a simple receipt is accepted as a proof of purchase, provided that the total amount including VAT and the VAT rate applicable to each item are clearly stated.
In France, an invoice made out to Zapptax is still required.
See also question: