SAP Migration Crisis: 60% of Projects Over Budget and Behind Schedule as 2027 Deadline Looms

Nearly 60 percent of SAP migration projects are running over budget and behind schedule, according to new research that highlights the mounting challenges facing organizations as they race toward the 2027 deadline for ECC support. The findings from ISG, based on a survey of 200 senior decision-makers at large global companies, paint a picture of widespread migration difficulties that threaten to leave thousands of businesses without critical support for their core ERP systems.

The research reveals that organizations consistently underestimate the complexity of migrating to S/4HANA, allowing project scope to expand uncontrollably while failing to account for internal constraints. These challenges are compounded by a surprising reluctance to re-engineer business processes during migration, with fewer than one in five organizations taking the opportunity to reimagine their SAP implementation.

The Legacy Support Cliff Approaches

SAP users face a critical juncture as mainstream support for ECC, the legacy ERP platform still used by thousands of the world's largest businesses, is set to end in 2027. While extended support at a 2 percent premium will be available until 2030, and SAP has discussed additional options beyond that date for customers who commit to migration plans early, the clock is ticking for organizations that have yet to begin their transition.

Gartner data shows that as of Q4 2024, 39 percent of SAP's 35,000 ECC customers worldwide had yet to migrate, nearly a decade after S/4HANA launched in 2015. This slow adoption rate is particularly concerning given the widespread project failures documented in the ISG research.

Brownfield, Greenfield, or Bluefield? The Migration Strategy Dilemma

The survey found that 34 percent of organizations were pursuing "brownfield" migrations, essentially lifting and shifting their existing processes to the new platform with minimal changes. Only 18 percent opted for a "greenfield" strategy, embracing SAP's preferred "clean core" approach with standardized processes. The remaining organizations chose hybrid "bluefield" approaches, mixing elements of both strategies.

Michael Dornan, ISG principal analyst, explained that even organizations attempting simple lift-and-shift approaches struggle with planning and execution. "Some of them are trying to do this quickly, a lift-and-shift as fast and cheap as possible. This group often underestimated the complexity, scope and the constraints they have. They also suffer from scope creep and changing requirements as they go through. A lot of the delays are caused by people, not necessarily the technology."

The Customization Trap

More than half of survey respondents acknowledged they had over-customized their legacy ERP systems to the point where standardization now feels risky to the business. This creates a significant psychological barrier to migration, as Dornan explained: "That's the fear they go through. If you standardize, then you just start that whole process again. There are a lot of stakeholders in the business that actually felt that their old ERP was doing the job that they wanted to, which creates inertia."

This resistance to change is particularly problematic as businesses look to leverage newer technologies like artificial intelligence. The report notes that "fragmented processes, extensive customizations, and legacy data structures often constrain which AI use cases can be effectively deployed after go-live. By contrast, environments with standardized processes and well-governed data are better positioned to realize the automation, forecasting, and operational efficiency gains enterprises expect."

Real-World Impact: The Airbus Example

The challenges documented in the research are playing out in real time at major corporations. Airbus, for example, currently runs a patchwork of SAP versions including legacy SAP R/3 4.6 and ECC 6.0 systems. While some divisions have already moved to S/4HANA, the company has indicated it may not complete its migration by 2030, well beyond the 2027 mainstream support deadline.

This cautious approach reflects a broader trend identified in the research: businesses are carefully weighing the risks of changing against the risks of staying the same. Of the total sample of SAP ERP users, eight percent planned to stay on ECC beyond 2027, while around two-thirds were still in the planning stage for migration, making it unlikely they would meet the mainstream support cutoff.

Implications for Business Leaders

The widespread migration failures documented in this research have significant implications for business leaders responsible for ERP strategy. The data suggests that organizations need to fundamentally rethink their approach to SAP migration, moving beyond simple lift-and-shift strategies to embrace more comprehensive transformation efforts.

Success appears to require not just technical expertise but also strong change management capabilities to overcome organizational inertia and resistance to standardization. Companies that fail to address these challenges risk not only project failures but also missed opportunities to leverage emerging technologies like AI that require standardized, well-governed data environments.

The 2027 deadline is rapidly approaching, and with 60 percent of migration projects already failing to meet budget and timeline targets, many organizations may find themselves facing difficult choices about whether to accelerate their migration efforts or accept the risks and costs of extended support arrangements.

For organizations still planning their migration strategy, the research suggests that investing in proper planning, change management, and process re-engineering may be more cost-effective in the long run than attempting to preserve legacy processes at all costs. The question is whether enough organizations will recognize this reality before the support cliff arrives.