SAP Migration · 5 min read · September 2025
A realistic SAP S/4HANA migration timeline, and what makes it longer
By Thinklytics Partners, SAP S/4HANA Practice
A mid-market S/4HANA migration typically runs 6 to 18 months. The single biggest cause of delay is data, with projects averaging about 30 percent longer than planned.
Topics covered
- Migration Timeline
- S/4HANA
- Planning
- Data Readiness
Frequently asked questions
How long does an S/4HANA migration take?
Typically 6 to 18 months for the mid-market and 18 to 36 months for large enterprises, depending on data volume, customization, and how clean the data is.
Why do migrations run long?
A 2025 Horvath study found only 8 percent of projects finished on time, with projects running about 30 percent longer than planned. Underestimated testing and data migration are the main causes.
What makes one migration faster than another?
Clean, governed data and little custom code. Both shorten the timeline dramatically. Ungoverned data and heavy customization extend it.
Can we shorten the timeline?
Yes, by measuring readiness before committing, remediating data before cutover, and keeping the data workstream senior and off the critical path.
Does a Blueprint add time?
It saves time. A four-week Blueprint up front prevents the mid-program revisions and data surprises that cause the largest delays.
When should we start?
Now. Mainstream ECC maintenance ends December 2027, and starting late compresses the timeline into a crowded, expensive window.