The transition to mandatory electronic invoicing through a Certified Provider is now in its final stage and will gradually apply to all businesses that carry out B2B transactions. The deadlines are clearly defined, and timely preparation is critical to ensure smooth compliance with the new regulatory framework.
Phase A – Mandatory use of a Provider by 2 February 2026
Phase A includes businesses that:
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Conduct B2B transactions
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Have an annual turnover exceeding €1,000,000
By 2 February 2026, these businesses will be required to issue their tax documents exclusively through a Certified Electronic Invoicing Provider. From that date onwards, only invoices transmitted to the Greek Tax Authority (AADE) via a Provider will be considered legally valid.
Phase B – Mandatory adoption for all B2B businesses by 30 September 2026
Phase B αφορά all remaining businesses that carry out B2B transactions, regardless of turnover, with a final deadline for mandatory compliance set at 30 September 2026.
Early preparation is particularly important, as it:
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Prevents last-minute implementation issues
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Ensures a smooth transition for accounting departments
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Reduces the risk of errors and penalties
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Allows sufficient time for testing and proper system configuration
What mandatory use of a Provider means in practice
The Electronic Invoicing Provider now represents a core pillar of tax compliance. Each business must ensure that:
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Invoices are issued in a legally valid manner
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Data are transmitted to the AADE in real time
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All technical and regulatory specifications are met
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Full compatibility with the myDATA platform is ensured
End-to-end support from AFS 📌
Mandatory electronic invoicing is not merely a technical upgrade; it is a combined process of tax, accounting, and IT compliance.
At AFS:
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Assess which phase your business falls under
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Guide you in selecting and implementing the appropriate Provider
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Ensure full tax and accounting alignment with the new framework
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Manage the entire transition process, minimizing the risk of penalties or operational disruptions
👉 Prepare in advance and secure a smooth transition to mandatory electronic invoicing with the confidence and expertise of AFS.
