Greece is modernising the way companies issue and report invoices with structured electronic invoices validated via the myDATA platform, now with extended deadlines.
The original go-live date of 2 February 2026 was moved to 2 March 2026, with a grace period extended until 3 May 2026. Each invoice receives a unique MARK number from myDATA.
Greece is modernising the way companies issue and report invoices. Under the reform, businesses must replace paper documents with structured electronic invoices that are validated and transmitted via the state's myDATA platform.
When the tax authority and the Ministry of Finance announced a delay in February, the original go-live date was moved and a grace period was extended. This gives companies more time to prepare their systems and to file the required declaration indicating whether they will use a certified e-invoicing provider or AADE's free tools.
The philosophy of the reform is that each invoice receives a unique MARK number from myDATA and that transaction data is automatically delivered to the tax office.
Decision A.1044/2026 splits the rollout into two waves:
Applies to companies whose 2023 turnover exceeded €1 million. During the transitional period from 2 March to 3 May 2026, these businesses may continue using paper or their existing invoice systems, provided they have filed the "Declaration of Electronic Issuing" or the "Declaration of Timologio Use".
Extends the obligation to all other taxpayers, with a soft-landing period through 31 December 2026. Covers domestic B2B, exports outside the EU, and B2G transactions. Intra-EU B2B transactions remain optional.
Important: From 2 March 2026 onward, recipients must be able to accept electronic invoices, except for certain state contracts and everyday expenses.
Businesses have several ways to comply:
Offer paid services to generate and transmit e-invoices, validate the XML structure, provide archiving, and integrate directly with ERP systems. This is the preferred option for large and multinational companies.
AADE's free solutions cater to freelancers and micro-enterprises:
Must either work through a certified provider or agree with their Greek counterpart on how the invoice will be exchanged. Non-resident suppliers should ensure their invoice carries a valid MARK identifier and uses a compatible XML format.
Invoices transmitted outside approved channels will not be considered legally issued.
| Violation | Penalty |
|---|---|
| Failing to issue e-invoice | Up to 50% of VAT due |
| Non-VAT transactions (simplified accounting) | €500 |
| Non-VAT transactions (double-entry bookkeeping) | €1,000 |
Missing the deadline can halt business processes, prevent input VAT claims, and force manual processing.
Generates structured e-invoices compatible with Greek requirements
Validates XML files before submission
Integrates with certified providers and myDATA
Tracks delivery status and stores documents for legal retention
Single platform for Germany, France, Greece and more
Note: Read more about required fields for invoices to Greece here — Required Fields in the Greek B2G e-Invoice (Peppol Greek CIUS)
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