SAP modules explained: a map of the SAP areas

Written by an SAP Finance & Treasury practitioner working with SAP since 2008 · how the guides are written · Updated 10 October 2026

SAP modules are the functional areas an SAP system is divided into, each with its own configuration, master data and specialists. Projects, teams and job adverts are organised by them.

What are the main SAP modules?

The main SAP ERP modules are the ones nearly every customer runs: finance and controlling, then procurement, sales and, for anyone who makes things, production. The rest are added by industry and size. The core SAP modules list reads FI (financial accounting), CO (controlling), SD (sales and distribution), MM (materials management), PP (production planning), QM, PM, PS and HCM on the business side, with Basis, ABAP and security on the technical side. The table gives the classic code, the line of business it belongs to in S/4HANA, and one transaction a beginner meets in the first week. Codes are given where they still work in S/4HANA; many tasks also have a Fiori app.

Front-office work sits partly outside the ERP: SAP Customer Experience covers commerce, marketing and the sales and service clouds, and is usually staffed separately from SD.

Not every customer runs every row. A bank or an insurer may run little beyond finance, HR and an industry solution; a distributor runs FI, CO, MM, SD and warehousing but no PP; a utility or a plant-heavy manufacturer leans on PM. Reading a job advert's module list against the employer's industry tells you which of them is the real centre of the project.

What do the SAP module abbreviations stand for?

The two- and three-letter codes abbreviate the component names SAP used in R/3 and ECC. FI is Financial Accounting, CO is Controlling, and FICO is the two together. MM is Materials Management, SD is Sales and Distribution, PP is Production Planning (in full, Production Planning and Control), PM is Plant Maintenance, QM is Quality Management, PS is Project System and CS is Customer Service. WM is Warehouse Management, EWM is Extended Warehouse Management and LE is Logistics Execution. HCM is Human Capital Management, called HR before it. TRM is Treasury and Risk Management. On the technical side ABAP is Advanced Business Application Programming, and BC, for Basis Components, is the code behind the word Basis. Searches for an SAP "full form" ask for exactly this list. The codes survive in S/4HANA as application component names, which is why a support incident about purchasing is still filed under MM-PUR although the line of business is now called Sourcing and Procurement.

What are SAP modules called in S/4HANA?

SAP itself no longer says "modules"; it organizes S/4HANA modules into lines of business — Finance, Sourcing and Procurement, Sales, Manufacturing, Supply Chain, Asset Management, Service — and sells the cloud editions as SAP Cloud ERP (public) and SAP Cloud ERP Private. Practitioners still say FI or MM, because a two-letter code is quicker than a product name and every job advert understands it. Behind the old codes, a few things did change for real:

• FI and CO share one table. The Universal Journal (ACDOCA) holds financial and management accounting line items together, and cost elements became G/L accounts, so the old FI–CO reconciliation work largely disappeared.
• Customers and vendors became business partners. The BP transaction replaces the separate customer and vendor masters that SD, MM and FI used to maintain.
• Warehousing moved to EWM. Classic WM is not the target in S/4HANA; Extended Warehouse Management, embedded or decentralized, is.
• HR went to the cloud.SAP SuccessFactors is SAP's main HR product; on-premise payroll and time continue in SAP HCM for SAP S/4HANA.

The S/4HANA career guide covers what those shifts mean for people who learned the ECC versions.

Which SAP modules are functional and which are technical?

Every module in the table above is functional: it models a business process and is configured by consultants who understand that process. Technical modules model how the system is built, run and protected, and they serve every functional area at once:

• Basis — installation, upgrades, transports (STMS), background jobs (SM37), performance.
• ABAP development — reports, enhancements, interfaces and forms, written in SE80 or in ABAP Development Tools for Eclipse.
• Security and authorizations — users (SU01) and roles (PFCG), with GRC on top for access risk and controls.
• Integration — SAP Integration Suite, whose Cloud Integration capability was formerly called CPI, alongside older SAP PI/PO landscapes.
• SAP BTP — the platform for side-by-side extensions, SAP Build and the AI services.
• Data and analytics — SAP BW/4HANA, SAP Datasphere and SAP Analytics Cloud.

Master Data Governance sits in between: functional in what it governs, technical in how it is built. The split decides the shape of a career more than the module does; functional vs technical sets out the difference in daily work.

How do the SAP modules connect to each other?

Through documents that start in one module and post in another. The three chains below are the ones every interviewer expects a candidate to walk from start to finish:

1. Order to cash. A sales order in SD checks availability against MM stock, the delivery is picked in the warehouse, and billing posts revenue and a receivable in FI. CO then reads the same postings as contribution margin.
2. Procure to pay. A purchase requisition becomes a purchase order in MM; the goods receipt updates stock and posts to inventory accounts; QM may block the stock for inspection; the three-way match in invoice verification releases the payable that FI pays.
3. Plan to produce. MRP in PP turns demand into planned orders, the production order consumes components from MM, CO collects and settles its costs, and PM keeps the machines running.

The hand-offs are configured, not coded. Account determination decides which G/L accounts a goods movement or a billing document posts to: inventory postings are set up in OBYC, revenue accounts in VKOA. Both tables are owned jointly by the logistics and finance consultants, and both are where a new valuation class or a new sales document type quietly breaks the books if only one side was told. Integration questions in interviews are usually about these settings, because they show whether a candidate sees past the edge of their own module.

Master data — the business partner, the material, the G/L account — is shared by all three chains, which is why a wrong setting in one module so often surfaces as an error in another. The SAP glossary explains the document and organizational terms these chains use.

Which SAP module should a career start in?

Start in the module closest to work you already understand, then grow into a neighbour that shares a process boundary — FI into CO, MM into EWM, PP into QM. Projects staff by module, so depth in one with a credible second reads better than a list of six. The first-module decision guide matches backgrounds to modules, and module combinations that work covers the second step.