SAP S/4HANA is SAP’s current enterprise resource planning (ERP) system and the successor to SAP ECC. It runs only on SAP’s in-memory HANA database, uses a simplified data model, and is designed for real-time reporting, the SAP Fiori user experience and built-in AI. It is available on-premises, in a private cloud or as a public cloud service.

If you run SAP ECC today, S/4HANA is where your SAP roadmap leads. SAP’s mainstream maintenance for ECC ends on 31 December 2027. Extended maintenance is available to 2030 at a premium, and a transition option runs to 2033 for some larger customers, but every route ends in the same place. The real question is how and when you move.

In this guide we explain what S/4HANA is, what changes compared with ECC, the ways you can deploy and implement it, and what a move involves in practice, including the data and design work that decides whether it goes smoothly.

What is SAP S/4HANA?

The name explains a lot. “S/4” stands for the fourth generation of SAP’s business suite, following R/2, R/3 and the ECC releases that came after R/3. “HANA” is SAP’s in-memory database, which S/4HANA was built to run on. SAP launched S/4HANA in 2015.

S/4HANA covers the same core business processes as ECC: finance, procurement, sales, manufacturing, supply chain, asset management and more. What changed is how it is built underneath.

Why SAP built it

ECC was designed in an era when databases stored data on disk and reading it was slow. To keep reports fast, ECC kept many separate summary tables, so the same figure was often stored several times and had to be kept in step.

HANA holds data in memory, which makes reading and calculating it far faster. That let SAP strip out most of those duplicate tables and build a leaner data model. The practical results are:

• Real-time reporting: figures are calculated from live transactions, so finance and operations see the current position without waiting for overnight batch jobs.
• A simpler data model: fewer tables and less duplicated data, which reduces reconciliation work.
• A modern user experience: SAP Fiori replaces most SAP GUI screens with role-based apps that work in a browser and on mobile.
• A foundation for AI: SAP’s Joule assistant and embedded AI features are built for S/4HANA’s data model and are delivered to S/4HANA customers.

The current releases

S/4HANA on premise and S/4HANA Cloud Private Edition share the same code. Since the 2023 release, SAP publishes a new major release every two years, with seven years of mainstream maintenance for each. S/4HANA Cloud Public Edition is updated by SAP twice a year, so its customers are always on the latest version.

What Changes When You Move from ECC

S/4HANA looks familiar in places, but several changes affect almost every ECC customer. These are the ones that shape the most project work:

• Business Partner replaces customer and vendor masters. Customers and suppliers become one Business Partner object with roles. Every existing customer and vendor record has to be converted, so duplicates and gaps need fixing first. Our customer master data guide includes a preparation checklist.
• One table for finance. The Universal Journal brings general ledger, controlling and asset accounting entries together in a single table, so finance has one version of the numbers.
• SAP Fiori becomes the main interface. Most day-to-day tasks move to role-based Fiori apps. Getting the most from them means deciding which roles see which apps, instead of switching everything on.
• Simplified logistics. Inventory, material requirements planning and credit management all run on the leaner data model, which speeds them up and changes some processes.
• Custom code needs reviewing. SAP publishes a Simplification List of what has changed. Custom ABAP that relies on removed tables or transactions must be adapted, rebuilt as an extension on SAP BTP or retired.

We cover these differences side by side, with what they mean for your migration, in our guide to SAP ECC vs S/4HANA.

S/4HANA Deployment Options

S/4HANA comes in three main forms. They share the same core business processes but differ in who runs the system, how much you can tailor it and how upgrades happen.

Where RISE and GROW fit

RISE with SAP and GROW with SAP are SAP’s subscription packages for moving to S/4HANA in the cloud. Each bundles the ERP with BTP, process tools and managed infrastructure. RISE is aimed mainly at existing SAP customers and usually comes with Private Edition. GROW is aimed at organisations new to SAP and comes with Public Edition. Our guide to RISE with SAP compares the two side by side and explains how to choose.

Three Ways to Implement S/4HANA

There are three broad approaches to getting onto S/4HANA. The right one depends on how well your current system serves the business, and how much of its history you need to keep.

• Greenfield (new implementation). You start with a fresh S/4HANA system built on SAP’s standard best-practice processes, then load the master data and open balances you need. It is the cleanest start and the best chance to simplify, but it means redesigning processes and retraining users.
• Brownfield (system conversion). You convert your existing ECC system to S/4HANA, keeping your configuration, custom code and transaction history. It is usually less disruptive for users, but it carries existing complexity into the new system unless you clean it up along the way.
• Selective data transition. A middle path. You build a new S/4HANA system and move across only the data, configuration and history you choose. It suits organisations that want a fresh design for some areas while keeping others, or that are merging several ECC systems into one.

Whichever approach you take, the quality of your master data and the amount of custom code you carry decide much of the effort. Our S/4HANA migration guide goes through planning and running the move step by step.

What an S/4HANA Project Actually Involves

The ERP is only part of an S/4HANA project. In the projects we support, four other workstreams decide how smoothly the move goes and how much value you get afterwards.

1. Getting the data ready

Every S/4HANA move depends on clean master data. Customer and vendor records have to be merged into Business Partners, duplicates resolved, gaps filled and inactive records archived. Material and finance data need the same attention. This work is often underestimated, because it only becomes visible when records fail conversion checks close to go-live. Starting it early, with clear ownership and governance, takes it off the critical path. Our data quality guide explains where to start, and Maextro keeps the data clean once it is fixed.

2. Rethinking integrations

Most ECC landscapes connect to other systems through SAP PI/PO, and SAP’s standard support for PI/PO also ends in 2027. Many organisations move their interfaces to SAP Integration Suite as part of the same programme. Our PI/PO migration guide covers how.

3. Keeping the core clean

An S/4HANA move is the best chance in years to reduce custom code. Every modification you carry forward makes future upgrades slower and AI harder to adopt. Rebuilding custom logic as extensions on SAP BTP keeps the system standard and easier to update. Our guide to SAP clean core explains the approach.

4. Designing for the people who use it

A technically perfect S/4HANA system still struggles if users find it hard to work with. Deciding which Fiori apps each role needs, and testing new processes with real users before go-live, does more for adoption than any amount of training at the end. Our guide to design thinking in SAP shows how this works in a project.

Five Questions to Answer Before You Start

These questions shape the scope, cost and timeline of an S/4HANA move. Answering them early makes every later decision easier.

1. What is your deadline? Map your current support position against the 2027, 2030 and 2033 dates, and decide which one you are actually working to.
2. Cloud or on-premises? Decide whether you want SAP to run the system (Public or Private Edition) or keep it in your own environment.
3. Greenfield, brownfield or selective? This depends on how well your current processes serve the business and how much history you need.
4. How clean is your master data? Profile customer, vendor and material records now, so you know the size of the clean-up before it lands on the critical path.
5. How much custom code do you have, and what does it do? Each piece needs a decision: adapt it, rebuild it on BTP or retire it.

Frequently Asked Questions

What does S/4HANA stand for?

“S/4” stands for the fourth generation of SAP’s business suite, and “HANA” is the in-memory database it runs on. The full name is SAP S/4HANA.

Is S/4HANA the same as SAP ECC?

No. S/4HANA is ECC’s successor. It covers the same core processes but runs only on the HANA database, uses a simplified data model, and introduces changes such as the Business Partner model, the Universal Journal and Fiori as the main interface.

When does SAP ECC support end?

SAP’s mainstream maintenance for ECC ends on 31 December 2027. Extended maintenance is available to the end of 2030 for an extra fee, and SAP offers a transition option to 2033 for eligible customers who move to SAP ERP, private edition.

Is S/4HANA a cloud system?

It can be. S/4HANA is available as S/4HANA Cloud Public Edition, S/4HANA Cloud Private Edition, or on-premises in your own environment.

What is the difference between S/4HANA Public and Private Edition?

Public Edition is a shared cloud service with standard processes, updated by SAP twice a year. Private Edition runs in a dedicated cloud environment, allows more tailoring, and lets you plan upgrades with SAP.

How long does an S/4HANA implementation take?

It depends on the approach, the size of the business and the state of your data. Smaller greenfield projects on Public Edition can take a matter of months. Large conversions with complex landscapes often run for a year or more.

Do I need to clean my data before moving to S/4HANA?

Yes. Customer and vendor records must be converted to Business Partners, and incomplete or duplicate records will fail conversion. Cleaning data before the move is far cheaper than fixing it after go-live.

Planning Your Move to S/4HANA

S/4HANA is where every SAP ECC customer is heading. The organisations that move most smoothly are the ones that treat it as more than a technical upgrade: they clean their data early, keep the core standard, rethink integrations and design around the people who will use the system.

We help SAP customers with the parts of an S/4HANA move that most often decide its success: master data readiness, integration, BTP extensions and user experience. If you are weighing up your options, talk to our team about where to start.