What mainstream maintenance actually covers
SAP ECC 6.0 mainstream maintenance ends on 31 December 2027 for Enhancement Packages 6, 7, and 8. If you are on EHP 5 or below, mainstream maintenance already ended in December 2025. Mainstream maintenance means SAP continues to issue legal-change corrections (tax tables, payroll law changes, country-specific VAT), security patches, and defect corrections under the standard licence agreement. After 31 December 2027, none of these are issued for ECC under standard terms.
The three converging risks
This creates three live risks: legal compliance risk (payroll tax tables and VAT rules stop being patched — your system gradually falls out of compliance with new legislation); security risk (unpatched SAP vulnerabilities become a live attack surface, with no SAP-issued fixes); and operational risk (any severe system defect becomes a customer-funded investigation rather than an SAP-covered fix).
Extended maintenance is available — at a cost
SAP offers extended maintenance for ECC through 2030 at an additional 2% of annual licence value per year, on top of the standard 22% fee. For a large ECC estate, this represents significant spend over three years — money spent on staying stationary, not on capability. The extended period delivers no new functionality.
What else ends in 2027
SAP Process Integration (PI) and SAP Process Orchestration (PO) — the integration middleware in the majority of ECC landscapes — lose mainstream maintenance on the same 2027 schedule. These connect SAP to CRM, billing, HR, third-party logistics, and banking systems. They must move to SAP Integration Suite on BTP as part of the transformation, not as an afterthought. SAP Solution Manager also transitions; organisations should plan the move to SAP Cloud ALM as part of the programme.
The planning horizon is shorter than it looks
A full-lifecycle S/4HANA implementation for a complex ECC estate typically takes 12 to 24 months from project start to go-live. A brownfield system conversion takes 9 to 18 months. Adding the time to build and approve a board-level business case — typically 3 to 6 months — means organisations who have not started assessment work in 2026 are already running tight to the margin. Organisations going live before the deadline are those who started readiness assessment work in 2024 or 2025.
The organisations that treat the 2027 deadline as an opportunity to modernise their SAP estate and capture the AI agent benefits S/4HANA enables will end up better positioned than their competitors. The deadline is real — but the opportunity it creates is also real.