What Is ERP? A Complete Guide to Enterprise Resource Planning

ERP (Enterprise Resource Planning) is software that connects the different parts of a business: finance, manufacturing, supply chain and sales into a single, comprehensive system. Instead of each department keeping its own spreadsheets or standalone software, everyone works from the same data in real time, which makes day-to-day operations faster, more accurate and easier to manage as a business grows.

What does ERP stand for?

ERP stands for Enterprise Resource Planning. Breaking the phrase down helps explain what the software actually does:

• Enterprise – the system is designed to serve the whole organisation, not just one department.
• Resource – it manages the things a business relies on to operate: money, materials, people, time and equipment
• Planning – it helps a business plan and coordinate how those resources are used, rather than simply recording what has already happened.

The term itself was coined in 1990 by the research and advisory firm Gartner, who used it to describe a new generation of business software that extended beyond the shop floor into finance, sales and every other part of the company.

What is ERP in simple terms?

The simplest way to think about ERP is as a single source of truth for a business. Picture a manufacturer where the finance team works from one spreadsheet, production planning works from a separate scheduling tool and the warehouse tracks stock in a third system. Numbers drift apart, nobody has a full picture and reconciling everything at month-end eats up hours.

An ERP system replaces that patchwork with one shared database. When a sales order is placed, production sees it instantly, purchasing knows what raw materials to order, finance can see the revenue forecast and the warehouse knows what’s due to ship, all from the same record, updated in real time.

How does an ERP system work?

A central shared database

At the heart of every ERP system is a single database that every department reads from and writes to. When one team updates a record, a stock level, a price or a customer address, everyone else sees the change immediately, removing the delays and errors caused by duplicate or disconnected data.

Modules

ERP software is organised into modules. Self-contained applications for specific business functions (finance, manufacturing, inventory and so on) that all plug into the same central database. Businesses typically start with the modules most relevant to them and add more as needs grow.

Real-time data and workflow automation

Because every module draws on the same live data, ERP systems can automate the handoffs between departments: a completed production job can automatically update stock levels and trigger an invoice, without anyone re-typing information into a second system.

Role-based access

Users see the information and functions relevant to their role, a shop-floor supervisor might see production schedules and work orders, while a finance manager sees ledgers and reports, all drawn from the same underlying data.

Common ERP modules

Most ERP systems are built from a similar set of core modules, though the exact mix varies by vendor and industry:

Finance and accounting

General ledger, accounts payable/receivable, budgeting and financial reporting. Usually the backbone of any ERP system.

Manufacturing and MRP

Production scheduling, bills of materials, works orders and shop-floor data capture, often built on the material requirements planning (MRP) logic described below.

Supply chain and inventory

Stock control, warehouse management, purchasing and supplier management.

CRM and sales

Order processing, quoting and customer relationship management, sometimes as a native module and sometimes via integration with a dedicated CRM.

Field service and project management

For service-led manufacturers, some ERP suites extend beyond the factory to manage engineers, job scheduling and servicing in the field. Exel’s EFACS E/8, for example, provides its Eagle Field Service Management module for exactly this purpose.

ERP vs MRP vs CRM

These three acronyms are often confused. The table below summarises the key differences:

	ERP	MRP	CRM
Name	Enterprise Resource Planning	Material Requirements Planning	Customer Relationship Management
Primary Focus	The whole business: finance, operations, supply chain, service	Production scheduling and material/component ordering	Sales pipeline and customer interactions
Scope	Company-wide	Manufacturing/production only	Sales and marketing only
Relationship	Can include MRP and CRM as modules	A precursor to and often a module within, ERP	Often integrated with or a module within, ERP

Types of ERP systems and deployment options

Cloud (SaaS) ERP

Hosted by the vendor and accessed over the internet, typically paid for on a subscription basis. Requires less in-house IT infrastructure and is now the most common deployment choice for new implementations.

On-premises ERP

Installed and run on a company’s own servers, giving full control over data, security and customisation. Often preferred by manufacturers with strict data-residency, compliance or integration requirements.

Benefits of ERP

• A single, accurate source of data across the whole business, reducing errors caused by re-keying information between systems.
• Better visibility for management, with real-time reporting instead of waiting for month-end reconciliation.
• Improved efficiency through automated handoffs between departments.
• Easier compliance and audit trails, since financial and operational records live in one traceable system.
• Scalability, modules can be added as the business grows, without replacing the whole system.

ERP in manufacturing and engineering

ERP has particular significance for manufacturers, because so much of its underlying logic: bills of materials, works orders, material requirements planning originated on the shop floor. A modern manufacturing ERP system typically manages:

• Bills of materials (BOMs) – the exact components and quantities needed to build a product.
• Routings – provide detailed information about the series of operations required to make a manufactured item.
• Engineering change control – tracking design revisions and ensuring production always works from the current specification.
• Traceability – recording batch, lot or serial numbers through the production process, which is essential.
• Subcontract and outsourced operations – managing work that leaves the factory and returns partway through production.

Mettis Aerospace, a Redditch-based forging specialist supplying components to Airbus, Boeing and Rolls-Royce, is a practical example of this in action. The company had used one system for finance and a separate system for production planning across its business units, a familiar version of the fragmentation problem ERP is designed to solve. Consolidating both onto a single ERP platform (EFACS E/8) brought financial and production data together on one shared database.

How much does ERP cost?

ERP pricing varies depending on deployment model, number of users and the modules required:

• Cloud/SaaS ERP is usually priced per user, per month, with lower upfront costs but ongoing subscription fees.
• On-premises ERP typically involves a larger upfront licence cost plus infrastructure and maintenance, but no recurring subscription, for the licence fees.
• Implementation costs such as data migration, configuration, training and change management are often a significant part of the total cost of ownership, regardless of deployment model.

How to choose the right ERP system

• Start with a clear picture of your current processes and where they break down.
• Check whether the system is built around your industry’s workflows (e.g. manufacturing, aerospace, engineering) or adapted from a generic package.
• Consider vendor stability and longevity.
• For UK businesses, check compliance features such as Making Tax Digital compatibility and whether support and pricing are UK-based.
• Weigh up hosted or on-premises deployment against your data, compliance and IT resourcing needs.

Is ERP right for your business? Signs you need ERP

• Different departments are working from separate spreadsheets or systems that don’t talk to each other.
• Month-end reporting takes days of manual reconciliation.
• It’s hard to get an accurate, real-time picture of stock orders or production status.
• Growth is being held back by manual processes that don’t scale.
• Compliance or traceability requirements (for example in aerospace or other regulated sectors) are difficult to meet with current systems.

Frequently asked questions

What does ERP stand for?

ERP stands for Enterprise Resource Planning, software that unifies core business processes such as finance, manufacturing and supply chain into one system.

What is ERP in simple terms?

It’s a single, shared system that replaces separate spreadsheets and standalone tools, so every department works from the same up-to-date information.

What are the 2 main types of ERP?

Cloud (SaaS), and on-premises.

What is the difference between ERP and MRP?

MRP (Material Requirements Planning) focuses specifically on production scheduling and material ordering. ERP extends that logic across the whole business, including finance and sales. MRP is often a module within a wider ERP system.

What is the difference between ERP and CRM?

CRM (Customer Relationship Management) focuses on sales and customer interactions. ERP covers the whole business; CRM functionality is often included as a module or integrated with an ERP system.

How much does an ERP system cost in the UK?

Costs vary by deployment model, user numbers and modules required. Cloud ERP is typically priced per user per month, while on-premises involves a larger upfront licence cost. UK businesses should also check whether pricing is quoted in pounds by a UK-based vendor.

What industries use ERP?

ERP is used across manufacturing, aerospace, engineering, automotive, distribution, food production and many other sectors, though the specific modules and configuration needed vary by industry.

Is ERP only for large companies?

No. While ERP originated with large enterprises, cloud deployment has made it accessible to small and medium-sized businesses and modular systems mean companies can start small and add functionality as they grow.