B2B e-invoicing mandate 2025-2026 — EU derogation

Until now, a Greek business could invoice another business (a B2B relationship) by PDF, as long as it reported the data to myDATA. That is changing: Greece is making structured electronic invoicing mandatory between businesses, in tiers from 2025. To impose it without asking the customer's consent — which the VAT Directive still requires — the state obtained a derogation approved by the EU Council. The technical rail is the proven one: accredited providers + myDATA.

History — from derogation to rollout

The key point is legal. The VAT Directive 2006/112/EC, at Article 232, says an electronic invoice can only be imposed with the recipient's consent. As long as ViDA is not in force, a state wanting to make B2B e-invoicing mandatory by right must obtain a derogation via an EU Council implementing decision (the Article 395 procedure). Greece followed that route — as Italy and Poland did before it — to build its B2B mandate on the already-deployed myDATA foundation.

2020-2024  | myDATA first: Greece makes data transmission (reporting) mandatory,
           | but NOT yet structured B2B e-invoicing as the only valid medium.
           | The B2B invoice can still be a PDF + myDATA.
           |
2023-2024  | Greece requests a derogation from Articles 218 and 232 of the VAT
           | Directive 2006/112/EC — needed to mandate B2B e-invoicing without
           | the recipient's consent, before ViDA enters into force.
           |
2024-2025  | The EU Council approves the implementing decision authorising Greece
           | to make B2B e-invoicing mandatory for a defined period. Greece
           | publishes its national timetable.
           |
2025       | Tiered start of the B2B mandate: large enterprises first, then
           | widening by size / turnover. Issuance via accredited providers,
           | systematic myDATA reporting.
           |
2026       | Progressive generalisation to all taxable persons. Convergence with
           | the B2G schedule: a single technical rail (providers + myDATA) for
           | B2G and B2B.
           |
2028-2030  | ViDA takes over: EU harmonisation of Digital Reporting, cross-border
           | DRR on 1 July 2030. The Greek model must converge toward intra-EU
           | near-real-time.

Governance — AADE + EU derogation

The B2B mandate is run by AADE, which operates myDATA, accredits the providers, and publishes the timetable A. decisions. The European legitimacy comes from the EU Council implementing decision authorising Greece to temporarily derogate from Articles 218 and 232. This derogation is time-bounded: it covers the window until the ViDA rules enter into force, after which the legal basis reverts to harmonised EU law.

Legal basis of the Greek B2B mandate
====================================

VAT Directive 2006/112/EC
  Art. 218 — what counts as an "invoice" (paper or electronic)
  Art. 232 — e-invoicing requires the recipient's CONSENT
             -> obstacle to a universal B2B mandate

To remove the obstacle BEFORE ViDA, a state must obtain a
DEROGATION (Council implementing decision, Art. 395 VAT).

  Greece -> requests derogation from Art. 218 + 232
         -> EU Council implementing decision (authorisation)
         -> national transposition (Law + AADE A. decisions)
         -> mandatory B2B e-invoicing, without recipient consent

After 2030, ViDA renders these derogations obsolete: the legal
basis becomes harmonised EU law (structured e-invoice by default,
Digital Reporting Requirements).

Schema — issuance, providers, myDATA

The B2B flow reuses the B2G architecture: the issuing business goes through an accredited provider that seals the invoice, transmits it to the recipient, and reports the summary to AADE. The novelty is not the pipe, it is the obligation: the structured invoice becomes the only valid instrument, the PDF no longer suffices.

• Issuer — produces an EN 16931 invoice (core + Greek national CIUS, myDATA classification).
• Accredited provider — seal, timestamp, transport to the recipient, myDATA reporting.
• Recipient — receives the structured invoice (no prior consent required, thanks to the derogation).
• AADE / myDATA — records it, returns the MARK, feeds the electronic books and the VAT return.

Greek B2B vs Italy, Poland, France

Adoption — 2025-2026 timeline

• Tiered approach: large enterprises and high turnover first, then widening to SMEs.
• Reuse of accredited providers: businesses already connected for myDATA and B2G shift naturally onto B2B.
• Rail convergence: a single technical ecosystem (paroxoi + myDATA) covers B2G and B2B, simplifying the rollout.
• ViDA horizon: the national timetable is set to converge with the 2030 cross-border Digital Reporting.

Common pitfalls

• Conflating myDATA with the B2B mandate. Being myDATA-compliant (reporting) does not mean issuing structured B2B e-invoices. The B2B mandate adds a distinct obligation on the invoice medium.
• Still sending B2B PDFs. Once the tier is reached, the PDF is no longer a valid B2B invoice; only the structured invoice via accredited provider is.
• Underestimating the derogation's time limit. The EU derogation is time-bounded and set to be replaced by ViDA — anticipate DRR convergence rather than freezing a purely national implementation.
• Missing the applicable tier. The timetable depends on size / turnover; check your entry date into the mandate so you are not late.
• Ignoring myDATA classification in the B2B invoice. The structured invoice must carry the classification codes (income/expense) AADE expects, or face rejection / discrepancy.

Cross-links

• Greece hub — full view
• myDATA — electronic books
• B2G mandate — accredited providers
• Accredited provider model
• myDATA — classification
• ViDA 2030 — DRR alignment
• AADE — official myDATA
• EUR-Lex — VAT Directive 2006/112/EC