CAFM vs CMMS vs IWMS vs EAM: The Differences

CMMS, CAFM, EAM and IWMS in one paragraph

A CMMS manages maintenance work: requests, work orders, preventive schedules, parts and labour. CAFM supports facility management: buildings, space, occupancy and building services, usually with maintenance included. EAM manages physical assets across their whole life, from acquisition to disposal, with finance in view. IWMS is a broader workplace platform that adds real estate, leases and projects. The difference matters because buying the wrong category leaves gaps or pays for unused scope.

The labels overlap and vendors use them loosely, so this guide gives each a sourced definition where one exists, compares their scope side by side, shows where data has to flow between them, and ends with a checklist. It is vendor-neutral; the only product section is the last one. Standards are cited as of October 2026.

What a CMMS is

A computerised maintenance management system is commonly defined as any software package that maintains a computer database of information about an organisation's maintenance operations. It helps maintenance staff know which machines need maintenance and where spare parts are, helps managers compare the cost of breakdown repairs with preventive maintenance, and helps verify regulatory compliance.

CMMS products come in several types: standalone systems for one plant or one maintenance team, maintenance modules inside a wider ERP or EAM system, and specialist variants such as fleet or medical-equipment maintenance systems. Typical CMMS functions include:

• Maintenance requests and work orders with priorities, statuses and sign-off
• Preventive maintenance schedules by calendar or meter, with checklists
• Asset list with location, make, model and serial number
• Spare parts with minimum and maximum stock levels
• Technicians, skills, shifts and labour hours
• Downtime, failure codes and reliability measures such as MTBF and MTTR
• Maintenance cost per asset, department and period

What CAFM is

Computer-aided facility management is commonly described as the support of facility management by information technology, centred on supplying information about facilities, and the term is often used interchangeably with CMMS. The difference is the starting point: a CMMS starts from assets and work, CAFM starts from buildings, space and the people in them.

Facility management itself has an ISO definition. ISO 41011:2024, quoted by ISO/TC 267, defines it as an 'organizational function which integrates people, place, and process within the built environment with the purpose of improving the quality of life of people and the productivity of the core business'. In Germany, the German Facility Management Association (GEFMA) runs GEFMA 444, a certification scheme for CAFM software products. Typical CAFM functions:

• Buildings, floors and rooms with areas and occupancy
• Space allocation, moves and desk or room booking
• Helpdesk for service requests from occupants
• Maintenance of building services, often through a built-in CMMS
• Cleaning, security, visitors, parking and other soft services
• Energy meters, waste and sustainability reporting

What EAM is, and how ISO 55000 frames it

Enterprise asset management is commonly described as managing the maintenance of physical assets throughout each asset's lifecycle, from design, construction and commissioning through operation and maintenance to decommissioning or replacement, across departments and locations. Where a CMMS asks what work is due, EAM asks what each asset is worth to the organisation and what it should cost over its life.

The standards behind EAM are the ISO 55000 family. ISO 55000:2024, the second edition, defines an asset as an item, thing or entity that has potential or actual value to an organisation, and asset management as the coordinated activity of an organisation to realise value from assets, normally balancing costs, risks, opportunities and performance. ISO 55001:2024 specifies requirements for an asset management system and can be certified; ISO 55002:2018 gives guidance on applying it, with a revision under way.

ISO 55001:2024 adds clearer requirements on decision-making, realising value from assets, asset management planning, risk and opportunities, data and knowledge, and life-cycle operations. None of that is a software feature in itself, but an EAM system is expected to hold the data those processes need: criticality, condition, life-cycle cost and the link to the financial asset register.

What IWMS means

IWMS stands for integrated workplace management system. Unlike facility management and asset management, it has no ISO or EN definition we could verify; the term comes from the software market. In this guide, IWMS means a platform that combines real estate and lease management, capital projects, space management, facilities and maintenance, and energy and sustainability in one system, which makes it, in practice, a superset of CAFM.

Because the definition depends on who is selling, treat IWMS as a label and test the scope. Ask an IWMS vendor to show lease accounting, project budgets and maintenance work orders on the same building, with the same data, in one demonstration. If any of those needs a separate product or integration, you are looking at a CAFM or a CMMS with extras.

Side by side: what each category typically covers

The acronyms describe where a product started, not where it stopped. Many CMMS products have added space and helpdesk features, many CAFM products include a full maintenance module, and EAM suites often include facility screens. That is why a scope comparison is more useful than a definition when you are writing a tender.

These are typical scopes, not rules; individual products vary. Use them to decide which questions to ask rather than to rule a product in or out:

• Maintenance work orders and preventive schedules: core in CMMS and EAM; usually included in CAFM and IWMS
• Spare parts and maintenance inventory: core in CMMS and EAM; often lighter in CAFM
• Space, occupancy and moves: core in CAFM and IWMS; rare in CMMS; sometimes in EAM
• Real estate portfolio and leases: core in IWMS; sometimes in CAFM; rare in CMMS and EAM
• Capital projects: core in IWMS; sometimes in EAM; rare in CMMS and CAFM
• Asset lifecycle cost, criticality and the financial asset register: core in EAM; limited in CMMS and CAFM unless linked to finance
• Energy and sustainability: common in CAFM and IWMS; sometimes in EAM
• Health and safety (incidents, permits, risk assessments): permits often in CMMS and EAM; incidents usually in a separate EHS system

Where they overlap: one asset, several lists

The practical problem with buying several categories is not features but data. The same boiler appears in the CMMS as a maintainable asset, in CAFM as a building service in a plant room, in the finance system as a fixed-asset register line, and perhaps in an IWMS as part of a leased building. Each list drifts on its own, and every year someone reconciles them by hand.

Worked example. A public body's CMMS holds 3,000 assets and its fixed-asset register holds 2,600 lines; 2,450 can be matched. That leaves 3,000 − 2,450 = 550 assets in the CMMS only, and 2,600 − 2,450 = 150 register lines with no maintenance record, 700 exceptions in total. At 10 minutes per exception the reconciliation takes 7,000 minutes, about 117 hours, or about €5,250 at an internal cost of €45 an hour, every year, before anyone fixes the root cause.

The 150 register lines with no maintenance record are the more serious finding: either the assets no longer exist and the balance sheet is overstated, or they exist and nobody maintains them. Our guide on maintenance and the balance sheet covers how to reconcile the two lists and the capitalise-versus-expense decision.

Which one do you need?

The real choice is often not between categories but between one integrated system and several specialist systems joined by interfaces. Specialist systems can go deeper in their own area, such as a GIS-based EAM for a water network. An integrated system avoids the reconciliation shown above, because the request, the work order, the asset record, the cost and the budget are the same records seen from different screens. Count the interfaces you would need to build and maintain, and who owns each one, before you count features.

Start from the organisation and its main risk, not from the acronym:

• A factory, workshop or single hospital engineering team whose risk is equipment downtime: a CMMS
• A council, ministry or university running many occupied buildings: CAFM with strong maintenance, or a CMMS plus facility screens
• A utility, transport operator or infrastructure owner managing networks over decades: EAM aligned with ISO 55001
• A large property portfolio with leases, projects and space strategy: IWMS
• An organisation that wants maintenance, facilities, the asset register and finance in one database: an ERP with CMMS, facility and asset modules, which removes the reconciliation in the example above
• Outsourced FM where the contract is the unit of control: CAFM or contract-operations functions with SLAs, KPIs and deductions

Selection checklist

Whatever the label, test these points with your own data during the demonstration:

• Is there one asset record shared by maintenance, facilities and finance, or several lists kept in step?
• Can a room-level request become a work order, and does the request close when the work order does?
• Do preventive schedules hold frequency, checklist and next-due date, and can you see what is due by site?
• Are costs captured per work order and reportable by asset, department and cost centre against budget?
• Can assets be recorded as parents and components for depreciation and replacement?
• Are compliance certificates and permits to work held against the asset, with expiry dates?
• Which interface languages are available, and how complete is each translation?
• Can you export every record and attachment at the end of the contract?

Where Skyline Nexus ERP fits

Skyline Nexus ERP is an ERP with maintenance, facility and asset modules in the same system as its accounting. The CMMS covers work order requests, work orders, PPM schedules, a Task List Library of checklists, permits, compliance records, contracts, warranty claims, spare parts with minimum and maximum levels, engineer skills and reports such as MTTR, MTBF, Downtime Analysis and Maintenance Costs. FMS adds buildings, floors and spaces, space allocations, move requests, service requests from QR codes that route to CMMS work orders, reservations, energy meters and waste logs, plus a Lease Ledger (IFRS-16) screen. Asset Management holds the register with parent and child components, depreciation, revaluation, impairment and disposal.

Contract Operations, the CAFM contract layer for outsourced FM with SLAs, KPIs, penalties and payment certificates, and the EHS module for incidents, hazards, risk assessments and CAPA, are available on request. In the Skyline Nexus ERP menu, BMS refers to a lessor-side property and leasing module (units, occupants, leases and rent billing), not to a building automation system. Try the free month or book a demo, and we will map your current CMMS, CAFM and asset lists into Skyline Nexus ERP with you.