Greek tax authority AADE has postponed the mandatory B2B e‑invoicing launch to 2 March 2026, with a two‑month soft launch ending 2 May 2026 for large resident businesses. All other resident taxpayers must adopt the system from 1 October 2026, and a new penalty regime and early‑adopter incentives have been announced.

Irish Revenue has clarified that for Phase One of its VAT Modernisation programme, a "large corporate" is defined by management by the Large Corporates Division rather than turnover. From 1 November 2028, all VAT‑registered businesses in Ireland must be able to receive structured e‑invoices, and those within scope must issue EN16931‑compliant e‑invoices and transmit data to Revenue. The programme introduces mandatory electronic invoicing and real‑time reporting for domestic B2B transactions.

Delaying VAT compliance while upgrading to SAP S/4HANA exposes companies to rework, higher costs, and regulatory penalties. Early integration of VAT and e‑invoicing solutions can prevent errors, reduce audit risk, and accelerate time‑to‑value. The article warns that legacy SAP ERP systems will reach end‑of‑support in 2027, urging firms to embed compliance from day one.