Greece confirms myDATA B2B Phase 2 from 12 October 2026 — all remaining resident businesses
AADE confirmed that from 12 October 2026 virtually all remaining resident Greek businesses must issue B2B invoices and related commercial documents electronically and transmit them to myDATA in real time. Phase 1 has applied since 2 March 2026 to companies with turnover above EUR 1 million, with a transition period that ran to 3 May 2026. Documents receive a unique invoice identifier (UID) from myDATA, making this a clearance-style validation model. Issuance is via a certified electronic data transmission provider or AADE's free tools (timologio, myDATAapp). The early-adopter incentive window for smaller businesses closed on 3 August 2026 — companies that onboarded at least two months ahead of their deadline qualify for 100% depreciation on e-invoicing equipment and software in the year of purchase and a 100% deduction on production, transmission and archiving costs for the first twelve months.