Start with the French platform rule
French businesses subject to VAT must prepare to issue and receive invoices through a state-approved platform route. Official guidance says all companies must be able to receive e-invoices from 1 September 2026, while SMEs and micro-companies issue from 1 September 2027. The software question is therefore not “free or paid?” first; it is “can this route transmit, receive and report correctly through a plateforme agréée or a compatible solution connected to one?”