🇻🇳 Vietnam - Invoicing Specifications (GDT e-Invoice)
Status: 🔴 Mandatory Clearance (For nearly all businesses) Authority: GDT (General Department of Taxation) System: Hoadondientu (Electronic Invoice System)
1. Context & Roadmap
Vietnam mandates a Clearance system where invoices must be authenticated by the Tax Authority before being sent to the buyer (for most companies). Crucial Distinction:
- Invoice with Code: Standard model. GDT generates a unique code for each invoice.
- Invoice without Code: Reserved for specific sectors (Utilities, Banking, Telco) with high volume and trusted ERPs.
| Date | Scope | Obligation |
|---|---|---|
| Active | All Businesses | Mandatory e-invoicing (Decree 123/2020). |
| Jan 1, 2026 | New Decree 70 | Stricter rules for e-commerce and POS integration. |
| Ongoing | VAT Reduction | 8% VAT rate extended until Dec 2026. |
2. Technical Workflow (Authenticated Invoice)
Invoicerr must connect to a T-VAN provider (Value Added Network) to reach the GDT.
sequenceDiagram
participant S as Invoicerr
participant TVAN as T-VAN Provider
participant GDT as Tax Authority
participant B as Buyer
Note over S: 1. Generate XML
S->>S: Map to Decree 123 Format
S->>S: Sign with Digital Cert (USB/HSM)
Note over S: 2. Request Code
S->>TVAN: Send Signed XML
TVAN->>GDT: Forward Request
GDT->>GDT: Validate & Assign Code
GDT-->>S: Return "CQT Code" (Tax Authority Code)
Note over S: 3. Finalize & Send
S->>S: Embed CQT Code in Invoice
S->>B: Send XML + PDF (with Code)
🧱 Key Components
- CQT Code (Mã của cơ quan thuế): A unique string generated by the GDT. Without this, the invoice is invalid (for the "With Code" model).
- T-VAN: Intermediary service providers licensed to transmit data to GDT.
- Digital Signature: Mandatory. Usually a USB token or HSM-based signature (local standard).
3. Data Standards & Requirements
A. Format: XML (Decree 123)
- Syntax: Specific XML schema defined by Circular 78/Decree 123.
- Signature: Must use a certificate issued by a Vietnamese CA.
B. Critical Fields
- Form Number (Mẫu số): e.g.,
1(VAT Invoice),2(Sales Invoice). - Symbol (Ký hiệu): e.g.,
C26...(C=Code, 26=Year). - Buyer Info: Tax Code (MST) is mandatory for B2B.
4. Adjustments & Errors (Form 04/SS-HDDT)
Correction is strict. You cannot simply delete an invoice.
- Form 04/SS-HDDT: Must be submitted to GDT to report errors.
- Adjustment Invoice: Issued to correct value/quantity (linked to original).
- Replacement Invoice: Issued to replace a wrongly issued invoice (linked to original).
5. Implementation Checklist
- T-VAN Connection: Partner with a local T-VAN provider (e.g., BKAV, Viettel, VNPT). Direct GDT connection is hard.
- Digital Signature: Support integration with local USB tokens or cloud signing services.
- Code Storage: Store the returned CQT Code and render it clearly on the PDF representation.
- Adjustment Logic: Build flows for "Adjustment" and "Replacement" invoices referencing the original ID.
6. Resources
- Official Portal: Hoadondientu.gdt.gov.vn