Legal Invoice Number
Demo video: Legal Invoice Number
The Problem
In many countries — especially Vietnam — invoices carry two different numbers: the system-generated sequence (INV/2025/0001) and the legal VAT invoice number issued by the tax authority or e-invoice provider (AA/25E 0000123). Odoo only tracks the system number.
When an accountant needs to find an invoice by its legal number — for a tax audit, customer inquiry, or VAT declaration — they have no field to store or search it.
What This Module Does
Adds a Legal Number field to customer invoices and credit notes. Simple and focused:
- Store the legal VAT invoice number right on the invoice form, below the system number.
- Search and filter invoices by legal number in the list view and search bar.
- Synchronize the legal number to become the invoice's primary number and payment reference (one-click action, restricted to accounting managers, with full audit trail in chatter).
- Track changes via Odoo's built-in tracking — every legal number edit is logged.
That's it. No unnecessary complexity.
Why It Matters
- Tax audits: auditors ask for invoices by their legal number, not your internal sequence.
- E-invoice integration: e-invoice providers (Sinvoice, VNInvoice, MISA, Viettel) assign legal numbers that need to be recorded back in Odoo. This module provides the field they write to.
- VAT declarations: reporting tools can reference the legal number for compliance.
- Customer inquiries: customers quote the number printed on their invoice, not your ERP sequence.
Technical Details
- Adds legal_number (Char, tracked, not copied) and old_number (Char, read-only) to account.move.
- Server action "Synchronize Legal Number" available from invoice list (accounting managers only).
- Visible only on customer invoices and credit notes (out_invoice, out_refund).
Editions Supported
- Community Edition
- Enterprise Edition
Installation
- Navigate to Apps.
- Search with keyword to_legal_invoice_number.
- Press Install.
Instruction
Instruction video: Legal Invoice Number
Add a Legal Number
After installing this module, the Legal Number field will be displayed on the invoice interface.
Add a Legal Number for this invoice and save it.
Manage invoices by legal number
On the invoices list, use the filter and grouping tool to categorize and search for an invoice using the Legal Number.
This software and associated files (the "Software") may only be used (executed, modified, executed after modifications) if you have purchased a valid license from the authors, typically via Odoo Apps, or if you have received a written agreement from the authors of the Software (see the COPYRIGHT file).
You may develop Odoo modules that use the Software as a library (typically by depending on it, importing it and using its resources), but without copying any source code or material from the Software. You may distribute those modules under the license of your choice, provided that this license is compatible with the terms of the Odoo Proprietary License (For example: LGPL, MIT, or proprietary licenses similar to this one).
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The above copyright notice and this permission notice must be included in all copies or substantial portions of the Software.
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