SAP Data Migration Statistics (2026): Adoption, Overruns, Data Work and Quality

Most published numbers about S/4HANA moves describe whole programs, not data migration on its own. This page separates figures tied to a named study from those that are not, and gives the population and year for each. Where sources disagree, we say so.

Key takeaways

Adoption: how far SAP customers have moved

SAPinsider's ERP Migration and Transformation 2026 report, based on 296 respondents surveyed between December 2025 and March 2026, is the most current large benchmark we found. Key figures:

• 55% of respondents report that they have completed an SAP S/4HANA or S/4HANA Cloud deployment, which SAPinsider stresses is not the same as completing a transition.
• Just over a third (34%) report having completed a transition to S/4HANA.
• 36% are still implementing, evaluating or building a business case; 4% report a project on hold, and 5% have no plans for S/4HANA.
• Among respondents, 26% use S/4HANA Cloud compared with 29% on a traditional deployment.
• 43% named SAP's AI announcements as the primary external factor shaping their ERP strategy, ahead of the maintenance deadline at 39%.
• 35% planned to switch before the end of 2026, a timeline SAPinsider called optimistic for any organization not already underway.

Source: SAPinsider, 2026 (n=296, fielded December 2025 to March 2026)

Source: SAPinsider, 2026

A separate Precisely and ASUG survey, released November 4, 2025, reports a different picture of the same movement. It finds 59% of companies are now fully or partially live on S/4HANA, up 13 percentage points from 2024. Automation adoption, by contrast, has plateaued at 57% as migration work pulls resources away.

On the 2025 SAPinsider survey, 55% said they would move to S/4HANA as quickly as possible rather than as part of a broader transformation, and system conversions rose to 49% of planned deployments.

Timelines and overruns

ASUG's 2026 research, based on 194 members, found the average go-live takes about 1.4 years. The approach changes the length. Brownfield conversions, chosen by 47% of respondents, averaged 15.8 months, while greenfield implementations averaged 20.2 months.

Source: SAPinsider summary of ASUG 2026 research

The 2025 Horváth study, which surveyed 200 executives at SAP-using companies in six countries, is the most cited source on schedule performance. Its findings:

• Projects took on average 30 percent longer than originally planned.
• The study's authors described late go-lives as the typical outcome rather than the exception.
• Fewer than one in ten companies that had already completed the transformation stayed within the schedule.
• A quarter of transformed organizations heavily overran budget, and another 40% strongly overran it.

Source: Horváth, April 2025 (n=200)

ISG's 2026 report reaches a similar overall figure. It puts nearly 60% of SAP migrations at risk of running over budget and behind schedule. Among ASUG's 2026 respondents who missed their dates, causes included business changes (55%), unexpected complexity (45%) and scope creep (42%).

Source: SAPinsider summary of ASUG 2026 research

Historical context, not SAP-specific: Bloor Research's 2011 follow-up survey found 38.3% of data migration projects overran or were aborted, with an average overrun cost of $268,000. The same source notes that the 2007 Bloor figure of over 80% is still quoted but is outdated.

Data work: where migrations get expensive

The 2025 SAPinsider survey asked respondents which factors most affected timelines. Data ranked high:

Source: SAPinsider, 2025 survey, as summarized in 2026

• A playbook from Kagool cites a 2026 SAP Data Management Report: 27% of respondents named business resource availability as a top migration challenge, while 22% named data quality. We could not locate the primary report, so treat these as secondhand.
• The same secondary source says 90% of surveyed organizations recognized that migration requires data and process transformation, and 50% believed more than half their data and processes must change.
• Gartner's prediction, as reported by a migration vendor, is that by 2027, more than 70% of recently implemented ERP initiatives will fail to fully meet their original business case goals, and as many as 25% will fail catastrophically. Gartner's primary text was not accessible to us.
• Precisely and ASUG describe data quality as a critical but often overlooked migration challenge. That release gives no percentage for it.
• On data cost, Gartner's figure of at least $12.9 million per year on average is based on 2020 research. Other sources quote different values, covered in the conflicts section below.
• One vendor guide advises that organizations with large data volumes or complex data structures should budget 10–15% of total project cost for data work alone. This is vendor guidance, not a measured result.

ISG's February 2026 research points to governance as the root problem. Its co-author argues that programs need clear delivery ownership and independent checks on data readiness and integration testing, rather than blaming the technology (enterprises need to explicitly define delivery ownership and maintain independent oversight of critical activities such as data readiness, integration testing and change management.).

Scope, approach and re-engineering

ISG's survey of more than 200 senior decision-makers at large organizations is the best current read on how much process change migrations include. Fewer than one in five organizations re-implement SAP processes and technology when they move to S/4HANA. Nearly half (49 percent) carry out little or no re-engineering, choosing instead to preserve legacy processes and data. ISG's view is that organizations that keep fragmented processes and legacy data structures are likely to find that AI cannot deliver as much benefit after the work is completed.

Source: ISG, February 2026

The Precisely and ASUG 2025 survey ranks the top barriers. Respondents cited business process change (49%), customizations (44%), and organizational resistance (37%) as the top barriers.

Source: Precisely and ASUG, November 2025

Testing and quality

Quality is where the Horváth respondents felt the pain most. Despite the time and budget overruns, most results did not meet expectations, with 65% reporting strong to very strong quality deficits. Secondary write-ups of the same study name scope creep, weak project management, and underestimated data migration and testing phases as causes; the primary press release leaves the detailed cause breakdown to the full report.

A Gartner-attributed figure, reported in a data-quality guide, says 59% of organizations do not measure data quality. That makes it hard to know how much bad data a migration is inheriting. The figure is secondhand and we have not confirmed it against Gartner's text.

For practical test-planning implications, see our S/4HANA migration by the numbers guide and our test data for S/4HANA page.

ECC deadlines and the installed base

The dates set the pressure. Mainstream maintenance for SAP ECC 6.0 ends December 31, 2027. For ERP 6.0 without an enhancement package, and enhancement packages 1 to 5, mainstream maintenance already ended on December 31, 2025. Optional extended maintenance runs through the end of 2030 and adds two percentage points to the existing maintenance fee. A transition option lets a select group of large, complex customers keep running ECC under a managed cloud subscription through the end of 2033.

• Reporting relayed from CIO, a Gartner projection estimated roughly 39% of the approximately 35,000 SAP ECC customers, about 14,000 organizations, had migrated to S/4HANA by the end of 2024. That 39% figure mixes licensed and migrated customers, so quote it carefully.
• SAPinsider estimates between 20,000 and 25,000 legacy SAP ERP customers have not yet licensed S/4HANA.
• On staffing, only 12% of SAPinsider's 2025 respondents planned to rely on internal teams alone.

Where the numbers conflict

• Horváth on-time rate. The primary press release says fewer than one in ten completed companies stayed on schedule. Secondary write-ups report only 8% of completed migrations finished on schedule. We use the primary wording.
• Horváth population. The primary release describes 200 top executives from six countries. A secondary summary describes 200 completed SAP S/4HANA migrations. The two descriptions of the sample differ, so check the full report before citing the population.
• Horváth's 60% headline. The release headline says 60% of companies exceed budget and schedule, while its body describes deviations on budget, schedule or quality. Those are different tests, so cite the one that matches your claim.
• Precisely and ASUG versus ISG. A test-data vendor reports that 30% of SAP migration projects are either delayed or over budget, even among organizations actively in motion. ISG's population is large organizations, while this figure covers organizations already migrating. The populations differ, so the numbers are not directly comparable.
• Gartner's data-quality cost. One source gives $12.8 million per year, another gives $15 million per year attributed to Gartner, and the most-cited version is $12.9 million. The values differ across sources, and the underlying research dates to 2020.
• Left out, untraced. We did not use figures we could not tie to a named study, such as one claim that data migration accounts for over 75% of implementation problems, or a per-sector failure share for discrete manufacturing. We also did not use an uncited 2021 claim that 64% of data migrations overrun their forecast budget.

What this means for your sign-off

• Treat deployment and completion as different milestones. A go-live does not mean the migration is complete. Ask for completion criteria in your readiness report, not just deployment status.
• Staff for data before you need it. Data landscape complexity leads the 2025 SAPinsider list at 56%. Put data owners, cleansing capacity and mock-load budgets into the sign-off package.
• Use a credible overrun range in your plan. With under 10% finishing on schedule in the Horváth sample, build contingency into test cycles and cutover rehearsals rather than assuming the plan holds.
• Put independent oversight on data readiness and integration testing. ISG's governance finding is that fragmented vendor accountability drives delay. Name one owner for acceptance criteria across integrators.
• Decide early how much process change you will accept. When ISG reports that nearly half of firms carry out little or no re-engineering, it signals a decision you should make deliberately, not by default. Our phase-by-phase migration testing plan shows where data validation sits.
• Plan for the deadline you actually face. Mainstream maintenance, extended maintenance and the 2033 option imply different timelines. Our ECC end-of-maintenance guide explains each path. For governance, see our SAP Testing Center of Excellence playbook.

Frequently asked questions

What share of SAP S/4HANA migrations finish on schedule?

In Horváth's 2025 study of 200 companies, fewer than one in ten companies that had completed the transformation had stayed within the planned schedule. Secondary sources report 8%, a difference we flag above.

How many SAP customers have deployed S/4HANA?

In SAPinsider's 2026 benchmark, 55% of respondents report that they have completed an SAP S/4HANA or SAP S/4HANA Cloud deployment, but just over a third (34%) report having completed a transition.

How much longer do S/4HANA projects take than planned?

Horváth's 2025 study found projects took on average 30 percent longer than originally planned.

Which data factor do practitioners name most often as a timeline driver?

In SAPinsider's 2025 survey, the complexity of the existing data landscape (56%) ranked first, ahead of custom code at 49% and data harmonization and cleansing at 44%.

When does SAP ECC mainstream maintenance end?

SAP's mainstream maintenance for ECC 6.0 enhancement packages 6 to 8 ends December 31, 2027. Extended maintenance is available through 2030 at an added cost.

How many migrations does ISG say re-implement processes?

ISG's 2026 research found that fewer than one in five organizations re-implements SAP processes and technology when they move to S/4HANA.

Sources

1. SAPinsider Benchmark Research: ERP Migration and Transformation 2026, SAPinsider, 2026
2. 5 Hard Truths About the 2026 SAP ERP Migration Landscape, SAPinsider, 2026
3. SAP S/4HANA Migration Timelines: The Average, the Range, and the Factors Behind Both, SAPinsider, 2026 (summarizing ASUG 2026 and SAPinsider 2025)
4. Study shows: SAP S/4HANA transformations rarely go as planned, Horváth, April 2025
5. Firms Moving to SAP S/4HANA Prioritize Short-Term Stability Over Long-Term Transformation: ISG Study, ISG, February 2, 2026
6. 2026 State of SAP Migrations Report, ISG, 2026
7. New Research Reveals SAP S/4HANA Migration Momentum, Despite Ongoing Automation Challenges, Precisely and ASUG, November 4, 2025
8. Precisely release: barriers to S/4HANA migration, Precisely, November 4, 2025
9. SAP HANA Data Migration: A Step-by-Step Playbook for 2026, Kagool, 2026 (secondary; citing a 2026 SAP Data Management Report)
10. ERP data migration: 55% deployed, 34% done, 16 months left, Datapace, 2026 (secondary; citing CIO and Gartner)
11. Why ERP Migrations Fail at the Data Layer: 9 Core Patterns, Clonepartner, 2025 (secondary; citing Gartner)
12. ERP Master Data Preparation: The Complete Migration Manual, Flapp, 2026 (secondary; citing Gartner)
13. Bad Data Is Costing You Millions, Here's How to Fix It, IPC, 2025 (secondary; citing Gartner)
14. The Consequences of Poor Data Quality, Actian, 2025 (vendor; citing Gartner)
15. The research is clear: Too many migration projects fail, Curiosity Software, 2025 (vendor; historical Bloor data)
16. SAP S/4HANA Migration Costs in 2026, Tachyon, 2025 (vendor guidance)
17. The Never-Ending SAP Migration: How to Fix It, Synthesized, 2026 (vendor; citing Precisely and ASUG)
18. SAP ECC end of maintenance 2027: what ends and what applies after, operayo, 2026 (citing SAP maintenance strategy)
19. End of maintenance for SAP ECC in 2027, IBsolution, 2026
20. SAP ECC End of Support 2027: What It Means and What to Do Next, Incorta, 2026

Last updated: October 28, 2026. Statistics are refreshed as new research is published.