SAP S/4HANA Migration Readiness Checklist: 10 Steps Before 2027

SAP Business Suite 7 customers are entering a critical planning window. SAP states that mainstream maintenance for covered core Business Suite 7 applications runs through the end of 2027, with optional extended maintenance available through the end of 2030. For organizations still operating SAP ERP 6.0, the practical question is no longer whether to assess SAP S/4HANA—it is how to build a migration plan that is realistic, evidence-based, and executable.

This SAP S/4HANA migration readiness checklist helps program sponsors, SAP consultants, architects, functional leads, and IT managers identify the work required before a conversion or new implementation can be planned with confidence.

What the 2027 SAP maintenance milestone means

SAP’s published maintenance strategy says mainstream maintenance for relevant SAP Business Suite 7 core applications ends on December 31, 2027. Optional extended maintenance is planned from 2028 through 2030 and carries a premium of two percentage points on the maintenance basis for the covered scope. Organizations that do not select extended maintenance, or reach its end, move to customer-specific maintenance.

This does not mean every company must complete an SAP S/4HANA go-live on the same date. It does mean leadership should understand the cost, risk, contractual, staffing, and innovation implications of each option. Treat 2027 as a portfolio decision milestone—not simply a technical upgrade date.

Source: SAP’s official maintenance strategy .

SAP S/4HANA migration readiness checklist

1. Confirm your maintenance position and business case

Document the exact SAP ERP release and enhancement package, database, operating system, add-ons, industry solutions, support entitlements, and contract position. Translate technical urgency into measurable outcomes such as process simplification, faster financial close, improved planning, better user experience, lower complexity, or access to newer capabilities.

Verify which systems and components are in scope.

Estimate the cost and risk of waiting, including extended maintenance.

Assign an executive sponsor and define outcomes beyond “complete the migration.”

2. Choose a transition path deliberately

The right path depends on business appetite, landscape complexity, required history, and desired process redesign. A system conversion can preserve more of the current environment. A new implementation can maximize standardization. A selective data transition can retain chosen history while redesigning other areas.

Compare paths against process fit, data retention, custom-code volume, integration risk, outage tolerance, regulatory requirements, timeline, and internal capacity. Record assumptions so the steering committee can revisit the decision when evidence changes.

3. Run SAP Readiness Check and assign the findings

SAP Readiness Check for SAP S/4HANA provides a system-specific view of important conversion considerations. SAP documents capabilities covering relevant simplification items and other technical planning inputs. The value is not the dashboard alone; it is converting each finding into an owner, decision, estimate, dependency, and due date.

Run the required data collectors in the source system.

Review simplification items with functional and technical leads.

Identify consistency checks and data corrections early.

Use effort rankings as planning signals, then validate them.

Source: SAP Readiness Check documentation .

4. Baseline custom code and define clean-core rules

Inventory developments, enhancements, forms, reports, workflows, interfaces, and modifications. Use usage, business value, compatibility, and available standard functionality to decide what to retire, remediate, replace, or move to an approved extension pattern.

Define clean-core guardrails before design begins: where extensions belong, how exceptions are approved, how APIs are governed, and how technical debt will be measured. Without explicit rules, a project can recreate yesterday’s complexity on a newer platform.

5. Reduce and govern the data footprint

Data migration is a business workstream, not just a loading activity. Profile master and transactional data, define retention obligations, identify duplicates and obsolete records, and assign data owners. Decide what will be migrated, archived, transformed, or kept accessible through an approved historical strategy.

Prioritize business partners, materials, finance, assets, open transactions, and organizational structures.

Set measurable quality thresholds and reconciliation rules.

Plan multiple mock migrations with realistic volumes.

Obtain business sign-off on cleansing and retention decisions.

6. Map integrations and external dependencies

Create an end-to-end inventory covering SAP and non-SAP applications, middleware, APIs, files, batch jobs, EDI, identity services, banks, tax platforms, warehouses, vendors, and analytics. Record owner, protocol, frequency, criticality, data sensitivity, monitoring method, and test evidence for every interface.

Pay special attention to undocumented integrations, manual monitoring, and dependencies on custom tables. These frequently become late cutover risks.

7. Use fit-to-standard to redesign processes

An SAP S/4HANA program should not automatically reproduce every legacy process. Use fit-to-standard workshops to compare current requirements with standard capabilities and explicitly classify gaps. For every proposed deviation, document the business or regulatory reason, value, lifetime cost, and upgrade impact.

SAP Activate organizes work through Discover, Prepare, Explore, Realize, Deploy, and Run phases, connecting scope, design, build, testing, deployment, and continuous improvement.

Source: SAP Activate methodology .

8. Design security, controls, and compliance early

Plan roles, segregation of duties, privileged access, identity integration, audit evidence, data privacy, encryption, logging, and emergency access during design. Include security and control owners in fit-to-standard workshops; waiting until user acceptance testing creates rework and weakens adoption.

9. Build an integrated testing and cutover strategy

Testing should cover end-to-end business processes across modules and external systems—not merely individual transactions. Define unit, string, integration, regression, performance, security, user acceptance, migration, and operational-readiness tests. Automate stable regression scenarios where the economics make sense.

Develop cutover as a timed runbook with entry criteria, accountable owners, reconciliation checkpoints, communication paths, rollback decisions, and hypercare coverage. Rehearse it and use every mock cutover to improve the plan.

10. Close the SAP skills and change-readiness gap

Map the skills required for architecture, functional design, data, integration, security, testing, operations, and business adoption. Compare demand with internal capacity and the project calendar. Create role-based learning paths early enough for people to practice and contribute to design decisions.

Consultants need more than feature awareness; they need end-to-end implementation judgment. Business users need scenario-based learning aligned to redesigned processes, controls, and responsibilities. Track proficiency and adoption, not only course completion.

A practical 90-day SAP readiness plan

Days 1–30: establish the baseline

Confirm systems, releases, contracts, owners, and governance.

Run initial readiness and custom-code assessments.

Inventory integrations, data domains, controls, and critical periods.

Define business outcomes and option-evaluation criteria.

Days 31–60: make the major decisions

Compare transition paths and target operating models.

Prioritize simplification items, custom-code remediation, and data cleanup.

Identify critical skills, partner needs, and resource conflicts.

Create initial release, testing, and environment strategies.

Days 61–90: build an executable roadmap

Validate scope, dependencies, estimates, and sequencing.

Create risk, assumption, issue, and decision logs.

Agree quality gates, funding checkpoints, and measurable outcomes.

Launch remediation, data-quality, and enablement activities.

Common SAP S/4HANA migration mistakes

Treating the program as only a technical upgrade. Process ownership, data, controls, and adoption determine value.

Keeping every customization “just in case.” Usage and business value should drive the decision.

Underestimating integrations. Hidden dependencies surface late without validated inventory.

Delaying data cleanup. Poor data expands testing, reconciliation, and cutover risk.

Training too late. Teams need skills to make design decisions, not only operate the finished system.

Using the 2030 option as a strategy. Extended maintenance may create time, but it does not replace a funded roadmap.

Frequently asked questions

Is SAP ECC support ending in 2027?

SAP’s maintenance statement applies to specified SAP Business Suite 7 core applications and says mainstream maintenance runs until the end of 2027. Coverage depends on product and release, so verify the exact landscape and contract instead of relying on a generic “ECC deadline.”

Is extended maintenance available after 2027?

SAP states optional extended maintenance for the covered core applications is available through the end of 2030, with a premium of two percentage points on the maintenance basis for the covered scope.

What is SAP Readiness Check for SAP S/4HANA?

It is an SAP-provided assessment that helps organizations understand important system-specific considerations for an SAP ERP 6.0 conversion to SAP S/4HANA.

How long does an SAP S/4HANA migration take?

There is no responsible universal estimate. Duration depends on scope, path, landscape, data, custom code, integrations, regulatory constraints, testing, deployment model, and team capacity. A readiness phase should establish an evidence-based range and its assumptions.

What should an SAP professional learn for an S/4HANA program?

Prioritize end-to-end process understanding, fit-to-standard analysis, simplification impacts, migration concepts, integration patterns, clean-core principles, testing, data quality, controls, and change adoption.

Start with evidence, then build the roadmap

The strongest SAP S/4HANA programs begin by replacing assumptions with system evidence, named owners, explicit decisions, and trained teams. Use this checklist to establish the baseline, surface the largest risks, and create a roadmap leadership can fund and workstreams can execute.

ZaranTech’s SAP S/4HANA end-to-end training helps professionals connect functional concepts with the full implementation lifecycle—from discovery and fit-to-standard through testing, deployment, and support.