In 2025, SAP introduced a new Clean Core maturity model that redefines how companies manage custom code. For organizations buried under decades of Z-code, the message is clear: upgrade safety and cloud agility depend on reducing custom code and protecting the standard.
What Is SAP Clean Core?
For years, SAP customers have built Z-code customizations into their ERP systems to meet specific business needs. While these modifications delivered value in the short term, they now create major challenges: upgrade delays, higher costs, and limited cloud agility.
“Clean Core” is SAP’s answer. It means keeping the ERP system as close to standard as possible while moving extensions and innovations outside the core. This approach reduces technical debt, accelerates upgrades, and ensures companies can take full advantage of cloud and AI innovations.
Why SAP Clean Core Matters
SAP has been signaling the Clean Core direction for more than a year. Last year, Forbes reported that SAP was already urging customers to “keep the core clean.” By Sapphire and TechEd, that message had become central to SAP’s transformation strategy.
In August 2025, SAP formalized its position by publishing a four-level Clean Core maturity model. This framework helps organizations evaluate their current state and define a roadmap for keeping ERP systems upgrade-safe.
The Four Levels of SAP Clean Core
SAP now defines Clean Core as a journey with progressive maturity levels:
- Level A: True Clean Core. ERP core stays standard, and all innovation runs outside.
- Level B: Side-by-Side Innovation. Extensions shifted to SAP Business Technology Platform (BTP).
- Level C: Streamlined Extensions. Some cleanup, but legacy code remains.
- Level D: Unmanaged Customization. ERP is cluttered with years of custom code.
Why Legacy Z-Code Blocks Clean Core Adoption
Legacy customizations may have solved problems in the past, but they now act as roadblocks:
- Upgrade pain. Every release cycle requires remediation.
- Limited agility. SaaS ERP models demand standardization, not custom lock-in.
- Cost leakage. IT spends more on maintenance than on delivering new business value.
Even SAP’s own Innovation Guide stresses that services and AI innovations only reach their full potential if the ERP foundation is clean.
LeapGreat’s Clean Core Approach
At LeapGreat, we have been helping organizations apply Clean Core principles long before SAP formalized them. Our approach focuses on:
- Protecting the standard. Avoid replicating outdated processes in new systems.
- Showing the system early. Visibility aligns stakeholders before complexity sets in.
- Aligning testing with business risk. Focus on what matters most to operations.
- Building stronger ownership. Customers must retain accountability, not outsource everything to integrators.
These themes came through strongly in our LinkedIn Live panel, “Inside S/4HANA Projects: Fixing Misalignment and Complexity” with:
- Sana Asher, ERP transformation specialist
- Patrik Fiegl, SAP partnerships leader at Tricentis
- Bernhard Lang, LeapGreat co-founder and former CEO of MSG Global
Together, they explored how real-world ERP leaders are tackling complexity while embracing Clean Core principles.
Watch the replay “Inside S/4HANA Projects: Fixing Misalignment and Complexity”
4 Steps to Achieve SAP Clean Core
The journey to Clean Core does not have to be overwhelming. Successful S/4HANA programs take a step-by-step approach:
- Inventory and assess. Use SAP’s Custom Code Migration tools to understand your current state.
- Prioritize by value. Retire unused code, and refactor only what drives business differentiation.
- Shift innovation. Move extensions onto SAP BTP using CAP or RAP frameworks.
- Enforce governance. Set clear rules to prevent Z-code creep from returning.
LeapGreat Clean Core Solutions: Version Zero and FrontLoad™
SAP provides the framework for Clean Core, but organizations often struggle with where to begin. LeapGreat makes the path tangible through two proven approaches.
- Version Zero (Phase Zero). Instead of starting with slide decks, LeapGreat sets up a working S/4HANA environment with real master data before kickoff. This exposes Z-code, data mismatches, and process gaps early, ensuring Clean Core goals are built in from day one. For a deeper dive, get the full guide: The More Modern Approach: A LeapGreat Guide to Value-Driven SAP S/4HANA Transformation.
- FrontLoad™. In just days, LeapGreat deploys a pre-configured S/4HANA system with best practices and your company data. This gives teams a “version of the future” immediately, so stakeholders validate Clean Core decisions in practice—not theory. Learn why the FrontLoad™ approach is a game-changer.
LeapGreat’s Edge
With Version Zero to uncover risks early and FrontLoad™ to align teams quickly, organizations can move faster, protect the standard, and build lasting momentum toward Clean Core.
Ready to Make Clean Core Real?
At its core, SAP’s Clean Core strategy is about freeing S/4HANA from the weight of decades of Z-code. Organizations that modernize now will unlock faster upgrades, cloud agility, and room for innovation.
LeapGreat accelerates this journey with Version Zero to surface risks early and FrontLoad™ to give teams a working future system on day one.
Contact us today about making Clean Core real in your S/4HANA program.
