SAP S/4HANA Pre-Conversion Technical Checklist
Most delays in a system conversion come from preparation items found late. This checklist groups the technical work to finish before you run SUM, with the blocking items marked critical.
0 of 33 items complete
16 critical items still open - these are the highest-risk gaps.
Scope and governance
Basis and infrastructure
Master data and finance
Custom code and interfaces
Data volume and testing
Close every critical item before the first production dry run. Open critical items normally become cutover risks.
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How to use this checklist
Assign each group to an owner: program management for governance, Basis for infrastructure, finance leads for master data and ledger items, development for custom code, and test leads for data volume and testing. Review the list at each steering meeting and use the critical flags to decide whether a dry run can start. Export the checked state to PDF or Excel to keep a record of readiness evidence for audit and sponsors.
- Review weekly during preparation
- Treat critical items as gates, not suggestions
- Keep evidence links for each closed item
The gates that stop a conversion
Four items most often stop a technical conversion outright: CVI synchronization errors, missing Unicode, add-ons without S/4HANA support, and unresolved errors from the Simplification Item Check. Finance consistency matters just as much, because reconciliation breaks found during conversion are far more expensive to fix than in advance. Resolve these first, then spend remaining time on custom code and data volume.
Dry runs and common mistakes
At least one full dry run on a recent production copy should measure real downtime and expose data issues that sandboxes with sample data hide. Common mistakes are skipping dry runs, converting a sandbox with unrepresentative data, and treating the Readiness Check as a one-time report. Also keep a rollback plan and backup validated before every production attempt.
Frequently Asked Questions
Is this checklist only for system conversions?
It is written for system conversion from ECC. For new implementations many Basis items do not apply, but master data, finance, custom code review and testing items still help.
How many dry runs are enough?
Many programs plan at least two or three on production copies. The right number depends on downtime targets, data volume and the number of defects found in earlier runs.
Who should own the critical items?
Give each one a named owner and date. Basis owns infrastructure, finance owns ledger items, and the data lead owns CVI. Shared ownership usually means nobody tracks it.
Can I reduce downtime with this list?
Indirectly. Archiving, clean data and tested procedures reduce runtime and rework. Techniques such as near-zero downtime options also exist, but check eligibility with SAP documentation.
If you want a second reviewer on readiness evidence before your first dry run, Netray can look at it with you.
Related Tools
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