A purchase order is a promise to pay for goods on agreed terms. The best purchase order software for small business turns that promise into a clear flow: request, approval, order, receipt, invoice. If you still raise POs in Word or Excel, you already know the problems: duplicate orders, missing approvals and invoices nobody can match.
The flow, and where software helps
Three-way matching, in one example
You order 100 units at 50 each, so the PO totals 5,000. Only 90 units arrive. The supplier invoices for 100 units, 5,000. A three-way match compares PO, goods receipt and invoice and flags the gap: you should pay for 90 units, 4,500, or ask the supplier for the missing 10. Good software does this check for you.
Tools compared
| Tool | Best for | License | Stack | Stars | Updated |
|---|---|---|---|---|---|
| ERPNext | Buying module with purchase orders | GPL-3.0 | Python (Frappe), MariaDB | 40,232 | Oct 2026 |
| Odoo Community | Purchase app in Community | LGPL-3.0 (Community edition) | Python, PostgreSQL | 55,072 | Oct 2026 |
| Dolibarr ERP CRM | Supplier orders for small teams | GPL-3.0 | PHP, MySQL/MariaDB/PostgreSQL | 7,732 | Oct 2026 |
| InvenTree | Purchase orders for parts and stock | MIT | Python (Django), React | 7,717 | Oct 2026 |
| LedgerSMB | Purchasing in double-entry accounting | GPL-2.0 | Perl, PostgreSQL | 570 | Oct 2026 |
| AureusERP | Newer ERP with purchasing | MIT | PHP (Laravel, Filament) | 12,073 | Oct 2026 |
Stars and dates are a snapshot from 16 October 2026. They show project activity, not quality. Tool names open our in-depth review.
Create purchase orders, receive goods and match supplier invoices inside a complete ERP.
- Leads, opportunities and quotations
- Accounting and inventory included
- Very large community
40,232 stars · GPL-3.0 · repo updated Oct 2026
Read the full ERPNext reviewOdoo Community includes a Purchase app for requests, orders and vendor bills.
- Huge app ecosystem
- CRM linked to quotes and invoicing
- Active community and partners
55,072 stars · LGPL-3.0 (Community edition) · repo updated Oct 2026
Read the full Odoo Community reviewDolibarr manages supplier orders alongside stock and invoices.
- Modular: enable only what you use
- Invoicing, stock and agenda built in
- Runs on cheap shared hosting
7,732 stars · GPL-3.0 · repo updated Oct 2026
Read the full Dolibarr ERP CRM reviewInvenTree supports suppliers and purchase orders tied to parts and stock locations.
- Suppliers, supplier parts and purchase orders
- Part tracking with categories, parameters and stock levels
- Stock control across locations with history
7,717 stars · MIT · repo updated Oct 2026
Read the full InvenTree reviewLedgerSMB handles purchase orders as part of its accounting and inventory features.
- Requests for quotation sent to vendors as PDFs
- Double-entry accounting with customer and vendor documents
- Quotations, orders and invoices
570 stars · GPL-2.0 · repo updated Oct 2026
Read the full LedgerSMB reviewAureusERP lists purchasing among its modules. Evaluate maturity before relying on it.
- Purchasing and procurement modules
- Modular ERP built on Laravel and Filament
- Inventory and warehouse features
12,073 stars · MIT · repo updated Oct 2026
Read the full AureusERP reviewData verified 16 October 2026. Each card opens our in-depth page for that tool.
How to choose
- You want purchasing, stock and accounting together: ERPNext.
- You make products from parts: InvenTree, which links suppliers, parts and POs.
- You already use Odoo: its Community Purchase app.
- You want a light suite: Dolibarr.
Set approval limits before you begin, otherwise purchase order software only adds paperwork. Pair it with a good supplier record, covered in our vendor management guide.
Example: a workshop ordering parts from five suppliers
An illustrative example, not a real company.
A workshop orders parts from five suppliers. Orders go out by email, deliveries arrive partially, and invoices rarely match what was ordered.
They move to purchase orders in their ERP. A technician raises a request, the owner approves above a threshold, and the PO goes to the supplier. When parts arrive, a receipt is recorded against the PO. When the invoice arrives, the system flags differences.
Fewer duplicate orders and fewer surprise invoices follow within a month.
Mistakes that cost small businesses time
- Raising POs after the order, as paperwork.
- No approval limits.
- Not recording partial deliveries.
- Paying invoices without checking the PO.
- Letting supplier prices live only in email.
Self-hosted vs paid: the honest trade-off
Paid procurement tools add supplier portals, catalogs and approval apps. For a small team, the purchasing module of an ERP gives most of the benefit. Add specialist tools only when volume and approvers multiply.
Self-hosted ERPs run on a VPS or hosting plan. A provider such as Hostinger is a typical choice, as long as the plan meets the project requirements.
Need a server to host it?
Self-hosting a CRM needs a server. PHP and MySQL apps can often run on ordinary web hosting, while Docker, Node, Python or Java apps usually need a VPS. Check each project's requirements first. Hostinger offers both shared web hosting and VPS plans.
Affiliate disclosure: this is an affiliate link. If you buy through it we may earn a commission at no extra cost to you. CRMs and software are listed independently of any hosting partner. Learn more.
Official links for the tools in this guide
Every tool above has its own page on our site with the full review. These are the official sources, so you can download the latest version safely.
- ERPNext: Official website · Source on GitHub
- Odoo Community: Official website · Source on GitHub
- Dolibarr ERP CRM: Official website · Source on GitHub
- InvenTree: Official website · Source on GitHub
- LedgerSMB: Official website · Source on GitHub
- AureusERP: Official website · Source on GitHub