2027 is a hard deadline for every organisation still running SAP ECC. SAP has confirmed that mainstream maintenance for SAP ECC ends on 31 December 2027, after which SAP will no longer provide standard support, security patches, or legal updates for the platform. For most companies, this means migrating to SAP S/4HANA is no longer optional. Below, we answer the most important questions about what this deadline means and what you should do about it.
What happens to SAP ECC when 2027 support ends?
When SAP ECC mainstream maintenance ends on 31 December 2027, SAP will stop delivering standard support packages, security patches, compliance updates, and bug fixes for the platform. Any organisation still running SAP ECC after that date will be operating on unsupported software, which creates real exposure in terms of security vulnerabilities, regulatory compliance, and system stability.
SAP has offered extended maintenance contracts in the past, but these come at a significant premium and only push the problem further down the road. They do not add new functionality, and they do not change the fundamental reality that SAP ECC is a legacy platform with no long-term future. Organisations that delay past 2027 will also find themselves competing for a shrinking pool of consultants and implementation partners, as the best talent shifts its focus entirely to S/4HANA.
The business risk is not just technical. Running unsupported software can affect your ability to meet audit requirements, satisfy insurers, and maintain contracts with partners who have their own compliance obligations. The 2027 deadline is not a soft recommendation. It is a firm end-of-life date that every SAP user needs to plan around.
What is the difference between SAP ECC and SAP S/4HANA?
SAP ECC is SAP’s previous-generation ERP platform, built on a traditional database architecture and designed for on-premise deployment. SAP S/4HANA is the current-generation platform, built exclusively on SAP’s in-memory HANA database, with a redesigned data model, a modern user interface called SAP Fiori, and significantly faster processing capabilities.
The differences go beyond technical architecture. S/4HANA simplifies the data structure that underpins core financial and logistics processes, which means faster reporting, real-time analytics, and a reduced footprint of custom code. Many organisations running SAP ECC have accumulated years of customisations and workarounds. Moving to S/4HANA is an opportunity to rethink those processes rather than simply lift and shift them.
S/4HANA is also the platform SAP is actively investing in. New features, integrations, and AI-driven capabilities are being built for S/4HANA, not for ECC. If your organisation wants to benefit from SAP’s product roadmap going forward, S/4HANA is the only viable path.
What are the options for SAP users facing the 2027 deadline?
SAP users facing the 2027 deadline have three realistic options: migrate to SAP S/4HANA, move to a different ERP platform entirely, or negotiate extended maintenance with SAP at additional cost. For most large organisations already invested in the SAP ecosystem, migration to S/4HANA is the most practical and strategically sound choice.
Migrate to SAP S/4HANA
This is the most common path. Organisations can choose between a greenfield approach, which means implementing S/4HANA as a fresh system with redesigned processes, or a brownfield approach, which converts the existing SAP ECC system to S/4HANA while retaining historical data and configurations. A third option, sometimes called a bluefield or selective data transition, combines elements of both. The right approach depends on how much of the existing setup is worth carrying forward and how much transformation the business wants to drive alongside the technical migration.
Switch to a different ERP platform
Some organisations use the 2027 deadline as a trigger to evaluate whether SAP is still the right platform for their needs. Microsoft Dynamics 365 is the most common alternative considered at enterprise scale. This path carries higher complexity and risk because it involves moving to a completely different data model and process framework, but for organisations where SAP has never been a strong fit, it can be the right long-term decision.
Extended maintenance
SAP has offered extended maintenance beyond 2027 for customers who need more time, typically at a higher cost and with limited scope. This is a short-term measure, not a strategy. It buys time but does not reduce the eventual migration effort.
How long does an SAP S/4HANA migration actually take?
An SAP S/4HANA migration typically takes between 18 months and three years for a mid-to-large enterprise, depending on the complexity of the existing landscape, the scope of business process changes, the quality of existing data, and the approach chosen. Greenfield implementations often take longer because they involve redesigning processes from the ground up, while brownfield conversions can move faster but carry more technical debt.
The most common mistake organisations make is underestimating the time needed for data migration, testing, and change management. The technical conversion of the system is rarely the bottleneck. What slows projects down is data quality issues discovered late, insufficient testing before go-live, and users who are not prepared for the new system when it lands.
Given that 2027 is the deadline and we are now in 2026, organisations that have not yet started their migration are already in a tight window. A realistic programme that begins today needs to move quickly through the assessment and design phases to have any chance of a controlled go-live before support ends.
What should organisations do first to prepare for the SAP deadline?
The first step for any organisation preparing for the SAP 2027 deadline is to establish a clear baseline of where you actually stand. That means assessing your current SAP ECC landscape, understanding the state of your data, mapping your existing business processes, and identifying the complexity of your customisations. Without this baseline, any migration roadmap is built on assumptions rather than facts.
This is exactly where a maturity assessment adds real value. Before committing to a migration approach, budget, or timeline, organisations benefit from an honest evaluation of their current ERP maturity, including their processes, data quality, and organisational readiness. This assessment surfaces the issues that would otherwise derail the programme later, and it creates a concrete starting point for a focused transformation strategy.
From there, the priority is to define your migration approach, build a realistic programme plan, and secure the right expertise. Given the complexity involved, most organisations need external support, particularly for cutover management and the phases that carry the highest operational risk. Waiting until 2027 is close to start planning is not a viable position. The organisations that navigate this transition well are the ones that start with clarity and move with purpose.
You can read about our full range of services to understand the breadth of support available for SAP transformations at every stage.
How Optinus helps with your SAP S/4HANA migration
We work with mid-to-large enterprises navigating exactly this challenge. Our consultants have hands-on experience from real SAP migrations at leading multinationals, not just theoretical frameworks. We cover the full transformation journey under one roof, from the initial maturity assessment through to post-go-live hypercare, so there are no handover gaps between specialisms.
- Maturity assessment to give you a clear, honest baseline before any budget or roadmap is committed
- Program and project management to keep your migration on track across all workstreams
- Data migration management with rigorous As-Is/To-Be analysis and testing to prevent data loss or errors
- Cutover management with real-time monitoring and hypercare to protect operational continuity at go-live
- Change management that addresses both the technical and human side of the transformation, driving genuine adoption across your organisation
- Available on-site and remote, across the Netherlands, Belgium, and internationally
If you want to understand where your organisation stands and what a realistic migration path looks like, get in touch with our team or learn more about what we do.
