Greece Postpones Second e-Invoicing Wave to November 2026

Greece has moved the second phase of mandatory e-Invoicing to November 2, 2026. Businesses with 2023 gross revenue of up to €1 million receive a transition period until January 31, 2027, before approved e-Invoicing channels become exclusive.

Greece has revised the timetable for the second implementation period of mandatory e-Invoicing, giving smaller businesses an additional month to prepare and extending the gradual implementation period until the end of January 2027.

The Ministry of National Economy and Finance and the Tax Authority (AADE) announced the change on September 30, 2026. AADE Decision A.1197/2026 amends the previous e-Invoicing implementation decision A.1128/2025 and formally postpones the timetable for businesses included in the second implementation period.

The revised timetable applies to the remaining businesses that were not covered by the first implementation period. In practice, this includes businesses with declared gross revenue of up to €1 million, determined on the basis of the income tax return for tax year 2023. The Tax Authority confirms that e-Invoicing for this second group becomes mandatory from November 2, 2026.

This is therefore a postponement and adjustment of the implementation timetable, rather than a change to the fundamental e-Invoicing model.

Mandatory implementation for second-period businesses begins on November 2, 2026, instead of October 1, 2026.

However, Greece is not requiring an immediate switch to exclusive e-Invoicing on that date. A gradual implementation period runs from November 2, 2026 through January 31, 2027. During this period, affected businesses can transition to the approved e-Invoicing channels while continuing to use existing methods of issuing and transmitting documents, including commercial or accounting software, ERP systems and the applicable myDATA data-entry method.

For businesses choosing an approved e-Invoicing provider, the implementation guidance requires the relevant Declaration of Commencement of Electronic Document Issuance and the business must begin electronic issuance during the transition period.

Businesses that use the Tax Authority free timologio or myDATAapp applications exclusively from November 2, without making use of the gradual transition, are treated differently under the published implementation guidance and do not need the same provider commencement declaration.

The distinction is operationally relevant because the period ending January 31 should not be understood as a general postponement of the mandate until February. November 2 remains the start of the second implementation period, February 1 is the date from which the permitted issuance and transmission channels become exclusive.

From February 1, 2027, affected invoices must be issued and their data transmitted to the myDATA digital platform exclusively through an approved e-Invoicing provider or the Tax Authority timologio and myDATAapp applications.

The requirement covers the transactions identified under the Greek mandate, including domestic B2B transactions, transactions with businesses established outside the European Union and relevant B2G transactions.

This changes the role of an ERP system in the process. An ERP may continue to form part of a company's invoicing environment and can be integrated with an approved e-Invoicing provider, but direct transmission of the covered invoices from the ERP to myDATA will no longer constitute an accepted alternative transmission route from February 1.

For retailers, this distinction is particularly relevant where the ERP or another central invoicing solution currently handles B2B invoices generated from retail operations. The change does not mean that ERP systems must be removed. Instead, businesses need to ensure that covered invoices ultimately pass through one of the permitted E-Invoicing channels.

Impact on retailers, ERP providers and e-Invoicing solutions

The postponement gives affected businesses more preparation time, but the main implementation work remains unchanged.

Retailers that issue B2B invoices from stores, central accounting systems or ERP platforms should identify where those invoices originate and how they currently reach myDATA. If transmission currently takes place directly through an ERP, the process needs to be reviewed before the exclusive-channel requirement applies.

ERP and retail software providers also need to confirm whether their solutions communicate with an approved E-Invoicing provider or support the required integration model. Simply having an existing myDATA connection does not necessarily mean that the system is prepared for the mandatory E-Invoicing route that applies from February 2027.

The transition period can therefore be used for provider onboarding, integration testing, invoice-flow validation and checking whether transaction and customer classifications are correctly mapped before alternative transmission methods are removed.

Separately, AADE has also postponed Phase B of digital goods movement reporting. Decision A.1198/2026 moves the start of the second phase, while the revised timetable provides for requirements relating to loading, transhipment, receipt and quantitative checks from January 1, 2027, with standardized item coding following from January 1, 2028.

What should impacted businesses do?

Businesses within the second e-Invoicing period should first confirm that they fall within the group entering mandatory implementation on November 2, 2026 and determine whether they will use an approved provider or the Tax Authority free applications.

Companies using ERP or commercial invoicing systems should review their current myDATA transmission architecture and verify whether covered invoices will be routed through an accepted e-Invoicing channel by February 1, 2027. Provider onboarding, declarations, integration work and testing should be completed during the gradual implementation period rather than postponed until the end of January.

Businesses affected by goods movement reporting should also treat January 1, 2027 as a separate implementation deadline and assess those requirements independently from E-Invoicing.

The most important practical distinction is between the start of mandatory implementation on November 2, 2026 and exclusive use of the approved channels from February 1, 2027. Treating February as the new start date would give businesses an inaccurate picture of the transition obligations.

For retail and ERP environments, the central issue is also not whether an ERP can continue to be used, but how it participates in the compliant invoice flow. Companies should therefore review the complete path from invoice creation to transmission to myDATA, rather than checking only whether their existing software can technically generate an invoice.

The principal official sources are AADE Decision A.1197/2026, which amends the timetable for mandatory E-Invoicing, and AADE Decision A.1198/2026, which postpones Phase B of digital goods movement reporting. Source

Ivana Picajkić, Medior Legal Consultant at Fiscal Solutions

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