If you do business in Greece, e-invoicing is no longer just a future project. It’s already shaping daily finance and tax operations.
Digital transmission of invoice and accounting data via myDATA Greece is mandatory, B2G e-invoicing is established, and B2B e-invoicing Greece becomes mandatory in phases in 2026, starting on 2 March 2026 for large businesses. The challenge is pulling Greece myDATA reporting, invoice exchange and exceptions into a single, auditable process your teams can run at scale.
In this article, we break down the Greece e-invoicing mandate, the role of AADE Greece, and the practical steps you can take to meet the e-invoicing requirements Greece sets in 2026.
TL;DR summary
- E-invoicing in Greece isn’t just about format changes, but about adapting to continuous, near real-time reporting through myDATA
- The 2026 B2B mandate increases pressure on businesses to build scalable, audit-ready workflows early
- A fragmented, country-specific approach creates long-term inefficiencies and visibility gaps
- A unified operating model across systems, teams, and countries is key to staying compliant as requirements evolve
What is myDATA, and why does it matter?
myDATA stands for “my Digital Accounting and Tax Application”. It is the platform run by AADE (Independent Authority for Public Revenue) that collects invoice and accounting data in real time or near real time.
In practice, this means Greece is not only moving companies towards structured e-invoicing. It is also enforcing digital reporting as a day-to-day operational requirement. For many finance and tax teams, the pressure point will not be the first successful submission but keeping reporting accurate and consistent once volumes rise, edge cases appear, and processes change.
If you are operating across multiple countries, this can create a familiar pattern:
- Local requirements that are easy to underestimate
- Urgent “just make it work” fixes in your systems
- Manual checks to avoid rejections and missing identifiers
- Limited visibility into what was actually reported, delivered and accepted
The good news is that Greece’s direction is clear. If you build the right operating model now, you can reduce the amount of rework later and ensure you are always compliant.
Greece e-invoicing requirements (B2B and B2G)
Greece has multiple layers of obligation, so it helps to separate reporting from exchange, and B2G from B2B.
Greece’s B2G e-invoicing requirements
For public procurement, Greece requires EN16931-compliant e-invoices, exchanged via Peppol. The public sector side must be able to receive and process structured invoices, and suppliers must issue and transmit them accordingly.
Greece’s B2B e-invoicing requirements
Structured e-invoicing for B2B is rolling out in phases:
- 2 March 2026:* mandatory for large companies with revenues exceeding 1,000,000 EUR in FY2023
- 1 October 2026: mandatory for all other businesses
*Update: The first phase has been postponed. AADE announced a staged implementation window from 2 March 2026 to 3 May 2026, allowing parallel use of business management software (commercial/accounting, ERP) or a special entry form. Obligated businesses must also submit either a Declaration of Commencement of Electronic Issuance of Documents or a Declaration of Use of the timologio application (effective date 2 March 2026).
What about B2C?
Structured e-invoicing is not mandatory for B2C in Greece. However, businesses still have to handle daily POS sales data reporting through myDATA.
The practical complexity: it’s not “just an e-invoice”
When teams talk about “e-invoicing in Greece”, they often mean one thing. In reality, Greece combines several moving parts:
Reporting to myDATA
The myDATA obligation sits in the background of domestic and cross-border activity. It also changes what “done” looks like internally. You need to know:
- What was reported
- When it was reported
- Which identifier(s) you received
- What failed, and why
Different channels depending on scope
Greece uses different rails depending on whether you’re invoicing the public sector or private businesses. B2G leans on Peppol. B2B exchange rules evolve, and the operational expectation is that reporting and delivery stay aligned.
Cross-border considerations
Cross-border transactions must be reported to myDATA. From 2026, structured e-invoicing also becomes mandatory for certain non-EU cross-border B2B flows, while intra-EU e-invoicing remains optional.
This is why compliance teams often struggle with a piecemeal approach. A local fix may solve one part of the process, but leave gaps in traceability, exception handling or audit readiness.
Checklist: how to prepare for e-invoicing compliance in Greece
Use the checklist below to pressure-test your Greece readiness, especially if you are approaching the March 2026 B2B milestone.
1) Confirm your scope
- Do you have B2G transactions in Greece?
- Do you have B2B transactions that fall under the phased mandate?
- Do you have B2C operations that create POS reporting obligations?
- Do you have cross-border flows that must be reported?
2) Align on the operating model
- Who owns compliance requirements: tax, finance operations, IT, or a shared model?
- Who monitors statuses and failures daily?
- What is the process for exceptions and corrections?
3) Check format and exchange requirements
Greece supports UBL 2.1 and local XML formats. For B2G, the exchange aligns with EN16931 and the Greek CIUS via Peppol.
4) Plan for audit readiness and retention
Archiving in Greece has a statutory retention period of 5+1 years, and archiving abroad is permitted within the EU if AADE can access records remotely during audits.
5) Build visibility early
Even before go-live, it helps to define what visibility means for your team:
- A clear audit trail from ERP invoice to submission, reporting and delivery outcome
- Searchable statuses and exceptions
- A single place to prove what happened, without stitching screenshots and spreadsheets
Where ecosio fits: one flow across reporting, exchange and exceptions
If you’re rolling out multiple countries, it’s rarely efficient to build and maintain a Greece-specific solution inside the ERP system.
ecosio’s Global E-invoicing Compliance (GEC) solution is designed to help you orchestrate the end-to-end Greece flow through a single platform, with validation, monitoring and exception handling built into the operating model.
At a high level, this supports an approach where you:
- Connect your ERP system once via API, SFTP or AS2
- Validate and convert invoice data into the required formats
- Transmit via the required reporting and delivery flows based on your scope
- Monitor outcomes and handle exceptions with clear ownership
FAQ: Greece e-invoicing requirements
Is e-invoicing mandatory in Greece?
myDATA digital reporting is mandatory for businesses. Structured e-invoicing is mandatory for B2G, and B2B becomes mandatory in phases in 2026.
Is Peppol mandatory in Greece?
Peppol is used for B2G e-invoice exchange. For B2B, Peppol is not currently the mandatory exchange route.
Are cross-border transactions included?
Yes, but the rules depend on scope:
- Reporting: both inbound and outbound cross-border transactions must be reported to myDATA, including sales (income) and purchases (expenses).
- Structured e-invoicing (exchange): From 2026, structured e-invoicing also becomes mandatory for certain non‑EU cross-border B2B transactions via certified providers, while intra‑EU cross-border e-invoicing remains optional.
Closing thought
If Greece is on your roadmap, the most valuable step you can take now is to align the business on scope and ownership. Once that’s clear, you can build multi-country e-invoicing compliance that stays robust as requirements evolve, without adding more country-specific complexity.
This is where a global e-invoicing solution and scalable e-invoicing architecture can help, especially when you need automated e-invoicing compliance across multiple jurisdictions.
For more information about compliance transactions in Greece, visit our country profile page. To learn more about how ecosio supports global e-invoicing compliance, get in touch now.
