Open-source ERP · For small and middle-market companies · Updated October 2026
Open-source ERP: what is actually free, and what it takes to run a business on it.
Open-source ERP software removes the license bill. It does not remove the work. This guide covers what a free open-source ERP license really gives you, what still costs money, how the main options differ, and what we learned running one in a live operation with more than 400,000 SKUs.
The short answer
Free is the license, not the project.
Open source means the source code is published under a license such as the GPL. You can run it, modify it and host it wherever you like, for as many users as you like, without paying the author. For an ERP that takes the largest recurring line out of the budget: the per-user subscription.
What it does not remove is everything that makes an ERP work in a real business: hosting, configuration, data migration, training, support, upgrades and the custom work the core does not cover. Those costs exist on every ERP. On an open-source ERP they are the only costs, and you choose who does them.
What you still pay for
The honest cost list.
Hosting
A server or cloud instance, backups and monitoring. Yours to choose, and yours to keep patched.
Implementation
Process design, configuration, security, testing and go-live. Installation is the easy part.
Data migration
Customers, vendors, products, stock and open orders. Data condition is the biggest driver of timeline.
Training
The floor and the office have to use it on day one.
Support and upgrades
Someone has to own version upgrades, user administration and troubleshooting.
Custom work
Whatever the core does not do. Built as separate modules, it survives upgrades; built into the core, it traps you.
The main options
Dolibarr, Odoo Community and ERPNext, side by side.
Search for a list of open-source ERP software, open ERP software or the top open-source ERP and three projects come up most, whether you want an open-source ERP for small business or a customizable open-source ERP. Facts from each project’s own site or repository, checked October 2026. Our production experience is with Dolibarr, so that column also reflects what we have run.
| Criterion | Dolibarr | Odoo Community | ERPNext |
|---|---|---|---|
| License | GPL v3 or later | LGPL v3 | GPL-3.0 |
| Paid edition | None. One edition, everything included. | Odoo Enterprise, US$24.90–$49.00 per user per month (yearly billing, first 12 months). | Managed hosting offered separately on Frappe Cloud. |
| Accounting | Included: double-entry ledger, bank reconciliation, reports. | Invoicing in Community; comprehensive accounting is Enterprise. | Accounting module included. |
| Inventory | Included: multi-warehouse stock, barcode, lot and serial tracking. | Inventory in Community; the Barcode app is Enterprise. | Order Management: inventory levels, replenishment and sales. |
| Manufacturing | Included: bills of materials and manufacturing orders. | MRP in Community; PLM and Quality are Enterprise. | Manufacturing module included. |
| Built on | PHP with MariaDB, MySQL or PostgreSQL. | Python with PostgreSQL. | Frappe Framework (Python and JavaScript) with MariaDB. |
| Extending it | Module framework and REST API. We run 26 custom modules with 1 core file changed. | Custom modules; Studio (no-code) is Enterprise. | Custom apps on the Frappe Framework. |
| Hosting | Self-host anywhere, or a partner cloud. | Self-host Community; Odoo Online and Odoo.sh come with Odoo’s own plans. | Self-host (Docker documented) or Frappe Cloud. |
What we learned running one
Open source scales when you extend it the right way.
Built-N-AI implemented Dolibarr as the operating system of TXS Corp, a hardware distribution and consumer-electronics resale business: more than 400,000 SKUs, up to 300 orders a day, Amazon and eBay orders arriving by API. Stock Dolibarr did not do all of that. Twenty-six custom modules did, and only 1 core file was changed, a logged fix for a Dolibarr defect that is isolated so it can be removed when Dolibarr corrects it.
That is the real advantage of open source for an operating business. You are not waiting on a vendor roadmap or paying for a module tier. If the warehouse needs paperless picking, you build paperless picking, and it is yours.
Honest guidance
When open source is the wrong call.
Nobody will own it
With no internal owner and no partner, upgrades and backups do not happen. A vendor-run cloud is safer.
Multi-subsidiary finance
Native consolidation across entities is a strength of commercial suites such as NetSuite.
You need one vendor accountable
Some boards, lenders and acquirers want a brand-name ERP with a vendor contract behind it.
The subscription is not the problem
If per-user fees are comfortable and the system fits, switching for license savings alone rarely pays.
Questions buyers ask
Open-source ERP, answered plainly.
What is the best open-source ERP for a small business?
It depends on the business. For a single-entity inventory business that wants every module free and a simple system to host and extend, Built-N-AI implements Dolibarr (GPL v3 or later, one edition). Odoo Community (LGPL v3) offers a broader app suite, with comprehensive accounting, the barcode app and Studio reserved for paid Odoo Enterprise. ERPNext (GPL-3.0) is built on the Frappe framework with accounting, order management, manufacturing, asset management and projects.
Is open-source ERP really free?
The software license is free. Running it is not: you still pay for hosting, implementation, data migration, training, support and any custom work. Built-N-AI’s Dolibarr implementation is a fixed $29,500 and managed support is $1,500 to $3,500 a month, with no per-user license fees at any user count.
What is the difference between open-source and free ERP?
Open source means the source code is published under a license such as the GPL, so you can run, modify and host it yourself. Free can also mean a free tier of a commercial product, such as Odoo’s One App Free plan, where additional apps or users move you to a paid subscription.
Can an open-source ERP handle a growing business?
Yes. Built-N-AI runs Dolibarr in a live distribution operation with more than 400,000 SKUs and up to 300 orders a day with no performance issues, extended with 26 custom modules and 1 core file changed.
Where can a self-hosted ERP run?
Dolibarr is web-based and runs on any server with PHP and a MariaDB, MySQL or PostgreSQL database, on-premise or as an open-source cloud ERP on infrastructure you control. ERPNext documents Docker-based self-hosting and managed hosting on Frappe Cloud. With self-hosting, backups, upgrades and security patching are your responsibility or your partner’s.
Dolibarr vs ERPNext: which is better?
We cannot give a hands-on verdict. Built-N-AI runs Dolibarr in production and has no production experience with ERPNext. On paper, ERPNext vs Dolibarr looks like this: both are open source (Dolibarr GPL v3 or later, ERPNext GPL-3.0). Dolibarr is PHP on MariaDB, MySQL or PostgreSQL; ERPNext is built on the Frappe Framework in Python and JavaScript on MariaDB. Choose on the skills you can hire or keep, the modules you need on day one, and a reference call with an operator your size who runs it.
What is the best free ERP software for small business use?
Look for a free ERP system for small business where the license itself is free at any size, not a free tier that ends when you add users or apps. Dolibarr is a free open-source ERP for small business with accounting, inventory and manufacturing in one edition. A low cost ERP for small business is not only about the license, so compare implementation and support too. Most lists of the best free ERP software mix both kinds, so check which one you are reading about.
Is there a free ERP for inventory management or manufacturing?
Yes. Dolibarr works as free ERP software for inventory management, with multi-warehouse stock, barcode support and lot and serial tracking in the core, and as open-source manufacturing ERP software with bills of materials and manufacturing orders. It also includes open-source ERP accounting software: a double-entry ledger, bank reconciliation and reports.
What are examples of open source ERP software?
The open source ERP examples that come up most are Dolibarr, Odoo Community and ERPNext. Lists titled “top 10 open source ERP” add more names, but these three open source ERP software examples cover most small-business shortlists. Each is a full open source ERP package, not a set of separate open source ERP tools: accounting, inventory, purchasing and sales in one install. The open source ERP companies behind them earn in different ways: Odoo sells a paid Enterprise edition, Frappe, the maker of ERPNext, sells managed hosting, and Dolibarr has no paid edition at all.
Is there a simple, web-based open source ERP with CRM and point of sale?
Yes. Dolibarr is web based ERP software open source under the GPL, it ships as Dolibarr ERP & CRM, and point of sale is in the free core, which also makes it open source retail ERP software.
Who should not choose an open-source ERP?
Companies that need native multi-subsidiary consolidation, want one large vendor accountable for hosting and support, or have no internal owner and no partner to maintain the system are usually better served by a commercial cloud ERP.
Sources: Dolibarr on GitHub, dolibarr.org, odoo.com pricing, odoo.com editions, ERPNext on GitHub. Checked 6 October 2026. Operating figures are from Built-N-AI’s live Dolibarr implementation at TXS Corp. Dolibarr, Odoo, ERPNext and Frappe are trademarks of their respective owners; Built-N-AI is an independent implementer.
Related ERP guides
Keep reading.
Compare
Dolibarr vs Odoo
License, real per-user cost, free-edition limits and upgrade path, side by side.
Cost
How much does an ERP implementation cost?
Published vendor ranges and the fixed-price Dolibarr implementation at $29,500.
Services
Dolibarr implementation and support
New and existing installs: implementation, custom modules, integrations and managed support.
Start with a conversation
What problem is costing you more than it should?
Let’s spend 30 minutes looking for the first problem worth solving.