What an SAP S/4HANA migration actually costs: the drivers, the ranges and where budgets break

You won't find one price for an S/4HANA migration here, because there isn't one. A single advisory firm puts the usual ECC 6 to S/4HANA move anywhere from £5 million to well over £100 million. What decides where you land is already sitting in your ECC system, and you can measure most of it before anyone sends a quote.

Most of these projects run over, and nobody should plan as if theirs won't. ISG's research this year found 58% of SAP migrations over budget and behind schedule. Only 15% came in on time and on budget. When Horváth asked 200 SAP customers, their projects were taking 30% longer than planned, and an ISG analyst said a lot of the delay comes from people rather than the technology.

Waiting has a price too. Gartner, as reported by CIO.com, counted about 14,000 of 35,000 ECC customers on S/4HANA by the end of 2024 and expects around 17,000 still on ECC in 2027. Forrester says demand for these projects is creating a skills shortage nobody can avoid. If half the market starts late, the people you need are likely to be booked up when you go looking.

Some of SAP's tooling costs nothing extra. The migration cockpit is embedded in S/4HANA at no additional cost, and SAP says the Business Transformation Center in SAP Cloud ALM is included in its support offering. The cost sits in the hours spent acting on what those tools find.

The compatibility scopedefinitionOld ECC functions SAP let you keep running inside S/4HANA for a while. Once that right runs out, you'll have to replace each one you still use. change catches people out. Some functions from ECC kept running inside S/4HANA under a temporary right of use. Once that right lapses, every one of them needs a replacement process or product, and that work lands on the budget of whoever is running the system.

Custom code is one of the two hardest parts, and usage data can shrink it. SAP's Custom Code Migration app uses that data to find extensions nobody calls, and those can be dropped during conversion instead of fixed. SAP recommends collecting it for six to eighteen months. If you start this quarter, the list is ready before the bids are.

Every customer and vendor record has to become a business partner, and SAP has a ten-unit training course on just this step. Records that fail the CVI master data consistency check have to be corrected before the conversion can run. Count those errors early, because someone in finance or master data will be correcting them by hand.

On RISE, the subscription is only part of the first year. Redress Compliance, a licensing advisor that works for buyers, says year-one cash cost is typically three to four times the RISE subscription. In one benchmark estate it modelled, RISE came out about $3.41 million more over five years than staying on ECC with extended maintenancedefinitionOptional paid support for ECC from 2028 to the end of 2030, priced as a premium on top of your normal maintenance fee.. Treat those as one advisor's numbers. They're still a good reason to model your own five years before you sign.

Buying time isn't free and it isn't wrong. DSAG's 2026 investment report says some members are accepting higher extended maintenance costs to get more time, and that skills shortages and tight budgets keep pushing schedules back. If you pay the premium, use the years to shrink the code and clean the data, or the project you start in 2029 costs what it would have cost now, plus three years of premium.

The path you choose moves cost between buckets. A system conversiondefinitionYou take the ECC system you already run and turn it into S/4HANA, history and configuration included. The alternative is a new implementation on a clean system. keeps your history and configuration, so in our view the effort centres on code, data and testing. A new implementation shifts more of it into redesign and data migration. Selective data transition sits between the two. In an analysis cited by SAP Learning of about 10,000 projects over three years, 48% were system conversions, so neither path is the odd choice.

# answer these before the bids go out
custom_code: usage data collected, unused objects listed
cvi_check: consistency errors counted by type, owner named
compat_scope: Note 2399707 report run, items in use listed
data_volume: archiving analysis done before HANA sizing
licence: users classified by FUE category in-house
mock_runs: at least two, timed, finance sign-off
# example output: your own answers go here

A well-scoped bid can still drift once the work starts. The drift tends to come from the same places a cheap bid hides its gaps, so that's where the guard rails go.

We do the measuring before you sign. We run the readiness check and a custom code analysis on a copy of production, read the simplification items against your modules and plan at least two timed mock conversions. See our SAP S/4HANA page, our S/4HANA engineers, or start with a free assessment.