Odoo modules and applications: what each one does

If you are comparing Odoo modules, the first thing to grasp is that Odoo is a suite of applications sharing one database, not a single monolithic program. Odoo itself speaks of around 50 main applications, with a community that has contributed more than 50,000 additional ones. You switch on what you need and leave the rest dormant.

This page walks through the Odoo features and applications domain by domain, flags what is native and what usually needs an extension or a specialist partner, and points out the checks that matter for a UK business: VAT, Making Tax Digital and payroll reporting.

How Odoo organises its applications

The Odoo documentation groups its applications into categories: Finance, Sales, Websites, Supply Chain, Human Resources, Marketing, Services, Productivity and Studio. Thinking in these families makes a project easier to scope, because each family tends to map to a department and to a phase of the rollout.

Two practical points shape the choice of modules:

• Dependencies. Some applications pull others in. Sales, for instance, relies on invoicing, and manufacturing relies on stock. A "one module" project rarely stays at one.
• Edition. Community is the open-source base on which Enterprise is built, and you can move from one to the other at any time. Some features you may expect sit only in Enterprise. See Odoo versions and editions before fixing a shortlist.

Finance: accounting, invoicing and expenses

The Finance category brings together Accounting and Invoicing, Expenses, online payment providers, fiscal localisations for more than 50 countries, and ESG tracking.

The Accounting application rests on automatic double-entry bookkeeping, bank synchronisation, bank reconciliation through reconciliation models, multi-currency with automatic rates, and multi-company with consolidation. It produces real-time reports: balance sheet, profit and loss, cash flow statement, partner ledger and ageing balances for customers and suppliers.

Stock valuation is handled either periodically (manual) or perpetually (automated), using standard price, average cost (AVCO) or FIFO.

UK points to verify. A localisation existing for a country does not mean every local filing is covered. Ask your integrator to show how VAT returns are prepared, how digital submission under Making Tax Digital works in your set-up, and how your accountant will access the books. Many UK firms keep their accountant in the loop, so check export and access arrangements early. For the detailed tour, read Odoo accounting and finance.

Sales: CRM, quotations, orders, point of sale

The Sales category includes CRM, quotations and orders, point of sale, subscriptions and rental.

• CRM tracks leads and opportunities through pipeline stages and feeds quotations directly.
• Quotations and orders turn an accepted quote into a delivery and an invoice without re-keying.
• Point of sale serves shops and counters and ties into the same stock.
• Subscriptions and rental suit recurring-revenue and equipment-hire models.

A distributor, a retailer and a service firm will use very different parts of this family. The page on Odoo sales and CRM explains how to configure it for each.

Purchasing, inventory and logistics

The Supply Chain category comprises Inventory, Manufacturing, Purchase, barcode, Quality, Maintenance, product lifecycle management (PLM) and Repairs.

For a trading business, the core trio is Purchase, Inventory and Invoicing. Purchase handles requests for quotation and supplier orders, Inventory handles receipts, transfers and valuation, and the barcode application speeds up warehouse work. Quality adds control points, and Maintenance covers equipment upkeep.

The details, including replenishment and warehouse design, are in Odoo inventory and purchasing.

Manufacturing

The Manufacturing application covers multi-level bills of materials, work orders and work centres operated from a tablet, a master production schedule (MPS), subcontracting, scrap, backorders, by-products, and lot and serial number tracking.

Enterprise adds advanced manufacturing features such as Shopfloor, a control centre and scheduling. If your shop floor needs finite scheduling or detailed quality gates, confirm in a demonstration that the Enterprise features meet the need, rather than assuming. See Odoo manufacturing and the wider manufacturing ERP guide.

Projects and services

The Services category includes Project, Timesheets, Field Service, Planning and Helpdesk.

This family is the natural centre of gravity for consultancies, agencies and installers. Compare it with the needs described in professional services ERP.

Human resources and payroll

The Human Resources category covers Attendances, Employees, Appraisals, Recruitment, Payroll, Time Off and referrals.

The Payroll application works out time worked from work entries drawn from contracts, Attendances, Planning or Timesheets, and then generates payslips. That is the engine; what matters for the UK is the statutory layer around it.

UK points to verify. Real-Time Information reporting to HMRC, pension auto-enrolment and statutory pay rules are specific to this country. Do not assume they come with the standard application. Many UK businesses run payroll in a dedicated payroll package and integrate it, while others extend Odoo with a localisation maintained by a partner. Read payroll software and RTI and Odoo payroll and HR before deciding.

Marketing, websites and productivity

Odoo also ships Websites, Marketing and Productivity applications. They are not the reason most firms choose an ERP, but they matter when the business sells online or runs campaigns: the same customer record then sits behind the website, the CRM and the invoice. If e-commerce is central, see e-commerce ERP.

Reporting, studio and AI

Reporting in Odoo is built into each application: the accounting reports above, plus lists, pivots and dashboards inside the sales, stock and project screens. Studio, which sits in its own category, lets you adjust screens and fields without code. The Custom formula adds Studio, agentic AI, multi-company and external API access, so a database that installs Studio or adds companies moves out of the free tier.

The page on Odoo pricing explains how users are counted: paying users are those with backend access, while portal users such as customers and suppliers are not counted as paying.

Mobile and everyday access

Odoo is used through a web browser, so staff can work from a laptop, tablet or phone. If warehouse staff or field engineers will rely on a phone or scanner, test that specific workflow during the demonstration. Barcode and Field Service are the applications to look at first.

The summary table: domain to module

What is native, and what needs an extension or a partner

A useful rule of thumb separates three layers.

1. Native and standard. The applications named above, configured not coded. This is where you want most of your project to sit.
2. Community or third-party add-ons. The community has contributed a large library, but quality and upkeep vary. Ask who maintains an add-on and what happens at the next upgrade.
3. Bespoke development. Needed for unusual processes or integrations with systems such as a bank feed, carrier or customer portal. Covered in Odoo customisation and Odoo integrations.

UK-specific items most likely to land in layers two or three are statutory payroll reporting, some tax filing routes and sector-specific rules. Your integrator should list them in writing, with an owner for each.

How to choose your modules without overbuying

1. List your processes, not the application names. Start from invoicing, replenishment, job costing or production routings.
2. Map each process to an application, and mark the gaps.
3. Decide the edition from the gaps, not the reverse.
4. Phase the rollout: the finance and stock core first, specialised applications afterwards.
5. Ask for a demonstration with your own data, including a VAT return and a payroll run if they are in scope.

Our guide to writing an ERP requirements document gives a structure for step one, and Odoo implementation shows how phasing works in practice. If Odoo does not seem to fit, Odoo alternatives compares other routes, and Odoo in the UK covers local considerations.

Get matched with an Odoo integrator

We do not implement Odoo ourselves and we are not affiliated with the publisher. ERP Integrator is a free service that puts you in touch with an integrator suited to your project, whether you are a small firm in London or a manufacturer in the West Midlands. How it works explains the process, and choosing an Odoo partner lists the questions to ask.

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