SAP & Enterprise Systems

SAP ECC to S/4HANA Migration for a European Manufacturing Group

A European manufacturing group with 2,400 users across 8 countries needed to migrate from SAP ECC 6.0 to S/4HANA before end of mainstream maintenance, consolidating 8 legal entities and 340 custom programs without disrupting production operations.

Industry: ManufacturingRegion: Europe (8 countries)Duration: 18 monthsServices: SAP S/4HANA, MDG, FI/CO, MM/SD
0
Hours of unplanned downtime during cutover
40%
Reduction in month-end close cycle time
2,400
Users migrated across 8 countries
18%
Under budget on total programme cost

Business Challenge

14 years of technical debt and a hard deadline

The client had been running SAP ECC 6.0 since 2010. With mainstream maintenance ending and extended support costs escalating, the board mandated a migration to S/4HANA within 18 months. The complexity was compounded by 8 legal entities operating on separate instances with divergent configurations.

Three previous migration attempts by other consultancies had stalled at the custom code remediation phase. ATMA Technology was engaged to rescue the programme and deliver a production go-live within the remaining 18-month window.

SAP ECC 6.0 approaching end of mainstream maintenance with 14 years of custom ABAP development
8 legal entities across 5 EU countries with different chart of accounts and fiscal year variants
Over 340 custom Z-programs requiring assessment, remediation, or decommission
Master data quality issues: 180,000+ material master records with inconsistent classification
Business continuity requirement: zero tolerance for downtime during peak manufacturing season

ATMA's Approach

Brownfield conversion with master data governance at the core

Phase 01

Landscape Assessment & Roadmap

Conducted a full custom code analysis using SAP Custom Code Migration Worklist. Classified 340 Z-programs into keep, remediate, and retire categories. Defined a phased migration roadmap with a brownfield conversion approach to preserve business logic.

Phase 02

Master Data Cleansing

Deployed SAP MDG to govern the master data remediation programme. Standardised material master classification, vendor and customer deduplication, and chart of accounts harmonisation across all 8 legal entities before technical migration.

Phase 03

Technical Migration & Testing

Executed 3 full dress rehearsal cutovers to validate migration scripts, data volumes, and cutover timing. Implemented a parallel run strategy for FI/CO to validate financial postings against the legacy system for 60 days post-go-live.

Phase 04

Hypercare & Stabilisation

Provided 8-week hypercare with on-site support across 3 primary sites. Delivered SAP Fiori adoption training for 2,400 users and established a Centre of Excellence for ongoing S/4HANA optimisation.

Technical Architecture

SAP Activate methodology with a data-first approach

The migration used SAP Activate's brownfield conversion path, preserving existing business processes while modernising the technical foundation. SAP MDG was deployed first to establish data governance before any technical migration work began.

The cutover strategy used a single-weekend go-live window with 72-hour hypercare on-site. Three full dress rehearsals validated the 6-hour cutover timeline before the production event.

Technology Stack

SAP S/4HANA 2023
SAP FI/CO
SAP MM / SD
SAP MDG (Master Data Governance)
SAP BTP
SAP Activate methodology
SAP Solution Manager
ABAP / Fiori
"Three consultancies had tried and failed before ATMA Technology. They came in, understood the complexity immediately, and delivered a zero-downtime go-live that our board had been told was impossible. The master data governance work alone has saved us hundreds of hours per month in reconciliation."
Group IT Director
European Manufacturing Group, 8 Countries

Planning your SAP S/4HANA migration?

Our SAP team has delivered migrations across manufacturing, financial services, and public sector organisations. Let's talk about your landscape.

ATMA Technology lideró una migración SAP ECC a S/4HANA sin tiempo de inactividad para un grupo manufacturero europeo con 2.400 usuarios en 8 países, entregada en plazo y por debajo del presupuesto.