SAP S/4HANA Deployment Options Explained: Greenfield, Brownfield, Hybrid

Introduction

One of the most critical decisions in the preparation (Phase Zero) phase for any SAP ECC to SAP S/4HANA programme is choosing the right upgrade path. Your choice shapes the DNA of your programme - influencing costs, risks, timelines, and the level of transformation that can be achieved. 

There is no “one-size-fits-all.” The best approach depends on your organisation’s vision, requirements for data, existing customisation levels, and appetite for change – to name but a few. 

The three main deployment paths are: 

• Greenfield (New Implementation) 
• Brownfield (System Conversion/Technical Upgrade) 
• Hybrid / Selective Data Transition (sometimes called Bluefield
   

1. Greenfield (new implementation)

A Greenfield implementation is a “clean slate” approach. It means re-implementing SAP from scratch, adopting SAP best practices, and redesigning processes. All historical SAP ECC customisations are left behind and need to be reimagined in the new world of SAP S/4HANA (this can include reverting to SAP standard or redeveloping extensions in a ‘clean-core' compliant fashion). 

Benefits: 

• Standardisation and simplification of processes. 

• Clean Core: opportunity to remove technical debt and avoid legacy inefficiencies. 

• Full flexibility to embrace innovations such as real-time analytics, AI, and cloud. 

• Highest potential ROI when aligned to a transformation vision 
  
  

Challenges: 

• High cost and resource effort (2–4 years typical timeline). 
• Significant organisational change impact and training requirements. 

Historical data migration is complex - requires decisions on what to archive, transform, or discard. 

Best for: Organisations seeking true transformation and productivity gains, not just an IT upgrade.

2. Brownfield (system conversion / technical upgrade) 

A Brownfield approach means converting your existing SAP ECC system to SAP S/4HANA while retaining much of your current configuration, processes, and historical data. Typically, this will be the quickest route to SAP S/4HANA (and it may suit a lot of companies) but at the expense of real transformation and potentially replicating the same inefficiencies that you experience today. 

Benefits: 

• Quicker and less disruptive than Greenfield (9–24 months). 

• Lower cost - preserves investments in existing ECC processes and interfaces, less time spent designing new processes.  

• Continuity of operations: minimal business disruption. 
  

Challenges: 

• Risk of “lifting and shifting” inefficiencies. 

• May stifle innovation if too much legacy customisation is retained. 

• Limited flexibility for adopting SAP’s cloud-first innovations. 

• On-premises focus - harder to take advantage of SaaS agility 

   

   

Best for: Organisations focused on cost, speed, and continuity. Businesses with relatively clean SAP ECC systems and strong process maturity, or those with heavily differentiated customisations that are not supported by SAP S/4HANA and not on the roadmap for the future.  

3. Hybrid / Selective Data Transition (Bluefield) 

A selective transformation that blends Greenfield and Brownfield approaches. Using third-party tools, organisations can choose which configuration, processes, and data to bring forward - and where to adopt new SAP S/4HANA capabilities. This is a good middle ground, allowing for innovation whilst balancing overall implementation costs, however, it can add to project complexity. 

Benefits: 

• Tailored flexibility: preserve differentiating processes while adopting SAP best practice in others. 

• Balanced risk: less disruptive than Greenfield, more modernisation than Brownfield. 

• Ability to cleanse and harmonise data during migration. 
• Strong option for large enterprises with complex requirements.
   

Challenges: 

• Requires additional tools and expertise (e.g., SNP, smart data transformation). 
• Can add programme complexity and costs if not well-planned.
  
  

Best for: Enterprises with a mix of legacy processes they want to retain and areas they want to transform. Organisations seeking a phased modernisation without full reinvention. 

Comparison at a Glance

How to Choose the Right Path

Your decision should consider: 

• Strategic Vision – Are you aiming for continuity or transformation? 

• Customisation Level – Is your SAP ECC environment clean or heavily modified? 

• Data Quality – How much data needs retaining, cleansing or restructuring? 

• Risk Appetite – Are you ready for a big bang change, or do you prefer phased modernisation? 

• Budget & Timeline – What can you realistically invest? 

Tip: We recommend to run the SAP Readiness Check and conduct a capability model assessment during Phase Zero. These provide objective insights to help guide your path. 

Conclusion

Choosing the right deployment option is one of the most critical decisions in your SAP S/4HANA journey. Ensure that during your preparation phase (Phase Zero) you evaluate these paths objectively, balancing ambition with pragmatism. There is no single “right” answer - but there is a right answer for your organisation.

For more on the this topic, also see related blog: SAP S/4HANA & Brownfield - the shortcut that will leave you short changed.