Greek e-invoicing from 1 February 2027: what changes and what to do now.

Four dates matter if you issue invoices from software, and the most critical is 31 January 2027. All of them are set in two AADE decisions published on 30 September 2026. Dates are day/month/year.

1 January 2027 concerns delivery notes, not invoices. It’s in the table because it usually involves the same software and the same people in the office, so it’s worth looking at both together. The next phase for delivery notes, B2 with item codes, starts on 1 January 2028.

Since 2 November 2026, e-invoicing is mandatory for businesses with revenue up to €1 million too. The larger ones, with gross revenue over €1 million in the 2023 financial year, went first, on 2 March 2026.

The obligation covers three kinds of invoice: sales to businesses in Greece, sales to customers outside the European Union except retail, and invoices to the public sector. Retail receipts and sales to businesses in other EU countries are not on this list.

Most businesses have already started. According to AADE, about 655,000 businesses, almost 70% of those with revenue under €1 million that issued an invoice in 2025, already issue their wholesale invoices through a provider or from AADE’s apps. Almost 488,000 of them joined in the last month before the announcement.

1 February 2027 changes things mainly for businesses that invoice from business software or an eshop that sends invoices straight to myDATA. If you already invoice through a provider or from timologio, nothing changes for you on that day.

The transition period to 31 January 2027 applies to businesses that filed the declaration of start of electronic issuing (Δήλωση Έναρξης Ηλεκτρονικής Έκδοσης Στοιχείων) in time, with a start date up to 2 November 2026. If you work with a provider, the provider usually submits it on myAADE, AADE’s online portal, and you accept it. If you issue only from timologio or myDATAapp, you don’t need it.

An e-invoicing provider (πάροχος ηλεκτρονικής τιμολόγησης) is a company licensed by AADE that issues, validates and sends your invoices to myDATA and to your customers. “Through a provider” means the invoice you issue passes through the provider first, and comes back to you with the MARK (the number AADE gives the invoice) and the QR code printed on it. Your software stays the same: it connects to the provider, and you keep issuing invoices where you issue them today.

As of 2 November 2026, no extension has been announced for 1 February 2027. The latest decision, A.1197/2026, allows sending straight from software to myDATA until 31 January 2027.

AADE has, however, moved the dates twice in 2026, by about a month each time. The first phase went from 2 February to 2 March 2026. The second went from 1 October to 2 November 2026, by a decision published on 30 September, one day before the old date. The end of the transition period moved with it, from 31 December 2026 to 31 January 2027.

So check the “Last updated” date at the top of this guide: we update this section with every new AADE decision. Don’t count on an extension. Connecting software to a provider takes a few weeks, and if the date holds, January will be busy for everyone.

If you issue a few invoices a month and already write them by hand, yes. AADE offers timologio, on the web, and myDATAapp, on your phone, free of charge. They cover invoices to the public sector too. But if your invoices come from software or an eshop, you’d be typing each one a second time by hand, and that’s where you need a provider connected to your software.

From 1 February 2027, an invoice written by hand, or sent from software straight to myDATA without a provider or AADE’s apps, counts as not issued. That’s how circular E.2004/2026 defines it, as AADE presented it in its press release of 17 February 2026.

The penalties are those of the Greek Tax Procedure Code:

• for transactions with VAT, 50% of the VAT of the transaction;
• for transactions without VAT, €500 if you keep single-entry books or €1,000 if you keep double-entry books, per tax audit.

The exception is a dropped connection. If the connection to the provider, or the provider’s connection to AADE, goes down, the invoice must be sent again within one day. That’s why your software’s connection must keep whatever didn’t go through and resend it on its own.

The answer depends on where you issue invoices today. In every case you keep your software and add the connection to the provider.

You use Odoo

If your Odoo sends invoices straight to myDATA today, that stops on 31 January 2027. We set up the connection to the provider inside Odoo: the invoice goes to the provider, and the MARK and QR come back to the document. Before you go live, we test credit notes and every document type you issue. See how we set up Odoo for companies in Greece. What has to be set up correctly in Odoo: Odoo and myDATA.

You have an eshop

Retail receipts are not part of mandatory e-invoicing, although they can also go through a provider instead of a cash register. Invoices, however, when the customer is a business with a VAT number, go only through a provider from 1 February 2027. So the eshop, on WooCommerce or another platform, needs a connection that issues an invoice or a receipt from every order, with a VAT-number check when the customer asks for an invoice.

You use another ERP

Ask the software’s vendor first whether it has a ready connection to a provider, with which providers and from when. If it doesn’t, or if that doesn’t cover you, the software can connect to the provider through eInvoice Link, our own e-invoicing platform, as long as it has an API or we can read its database. You don’t need to replace it; if you’re thinking about Odoo, you can move later, step by step.

We are not a provider. We work with licensed providers and connect your software to them, so that if the connection drops, the invoice waits and is resent without being lost. There’s more on the page about Greek e-invoicing through a provider.

E-invoicing isn’t only about the invoices you issue, but also those you receive. Since 2 March 2026, every business must accept its suppliers’ invoices electronically, even if it issues only a few itself.

If you have business software, these invoices can go straight into it as draft purchases, instead of being typed in by hand. Those still arriving as PDF or on paper can be read by AI, with a check on every line. If you issue from timologio, ask your accountant how you’ll receive them and where they’ll find them.

The seven points, in the order you do them:

1. List where each document comes from. Invoices, credit notes, receipts, delivery notes: which software issues each one today.
2. Find out whether your software sends straight to myDATA. If it does, that stops on 31 January 2027.
3. Choose timologio or a provider. For a few invoices by hand, timologio is enough. For a provider, check AADE’s list: whether it supports invoices to the public sector and connection to POS terminals, if you need them, and whether it connects to your software.
4. Check the start declaration and the authorisation. If you work with a provider, the start declaration must have a start date up to 2 November 2026, and the provider needs an authorisation through Taxisnet, the Greek tax portal. If anything is missing, talk to your accountant straight away.
5. Connect and test. Issue test invoices and credit notes, see the MARK and QR come back, and test what happens if the connection drops.
6. Sort out your suppliers’ invoices. Decide where you’ll receive them, ideally straight into your software.
7. Set a switch-over day with your accountant. Show them the tests, and move to the provider before 31 January 2027, not in the last week.