Choosing Your Path to S/4HANA: Fit-Gap Analysis and the Greenfield-Brownfield Decision

The transformation-approach decision and the support-timeline question are more connected than they might first appear. Basis Technologies' adoption modeling shows the share of the ECC and early S/4HANA installed base falling outside mainstream support climbing from 33% at the end of 2025 to 55% by the end of 2027. Organizations that delay a clear fit-gap decision aren't only delaying the migration itself. They're increasingly delaying it into a window where they're paying for extended or premium support on the system they're trying to leave.

Making the approach decision earlier doesn't remove the pressure a fixed deadline and a shrinking support window create. But it does give a program a credible basis for its timeline and its budget, built on an actual inventory of what has to change rather than a rough estimate. For many programs, that turns out to be the single biggest lever for keeping a transformation realistic from the start, and a faster fit-gap pass, helped along in part by AI matching tools, is one way to reach that decision sooner.

of the SAP ECC/S4 installed base is projected to fall outside mainstream support by the end of 2027, up from 33% at the end of 2025. (Basis Technologies)

An AI-assisted match against the simplification list can tell an organization, with a high degree of confidence, which items are technically in scope. It can't tell them whether a given process change is acceptable to the business, what the change-management cost of a given redesign will be, or which of several technically valid options best fits the organization's actual appetite for process change versus technical risk. Those remain executive and functional-leadership decisions. The tooling works best when it's framed that way from the start: a way to reach the real decisions faster, not a substitute for making them.