What does it mean when an invoice is rejected for a code?
An invoice that has been rejected for a code is a data message that has not passed the verification step required for code issuance by the tax authority's system. From July 1, 2026, the direct legal framework for electronic invoices is the Law on Tax Administration No. 108/2025/QH15, Decree 254/2026/ND-CP, and Circular 91/2026/TT-BTC. Appendix IV of Circular 91/2026/TT-BTC promulgates Form No. 01/TB-KTDL, which includes a notification that an invoice does not meet the requirements for code issuance and states the reasons for refusal, allowing the seller to take appropriate action.
Are invoices that haven't been assigned a code valid?
For electronic invoices that require a code, if the data file has not yet been assigned a code by the tax authority, the issuance process is incomplete. Businesses should not send this file to customers, consider it a valid invoice, or use it as a basis for tax declarations. Errors must be corrected and resubmitted until the code assignment status is successfully received.
To understand the difference between invoices with and without codes, readers can refer to the following article. What are electronic invoices and how are they classified?.
Common reasons why invoices are rejected for code issuance
The cause often lies in required data, registration information, digital signatures, invoice timing, XML structure, or connection status. The specific error code in the tax authority's notification is the primary basis for resolution.
The original article listed the data groups to be checked, including seller information, buyer information, tax identification number, date of issue, tax rate, total amount, sample number, symbols, and XML structure. The rewrite retains these groups but does not repeat character limits or technical rules unless there is a corresponding error message or technical documentation.
| Error group | Common symptoms | How to check |
|---|---|---|
| Seller information | The tax identification number, name, address, symbol, or model number do not match the registration records. | Compare the configuration data with the information already approved by the tax authorities. |
| Buyer Information | The tax identification number has an incorrect structure, or the name or address does not match the required field. | Review the documents, contracts, and tax identification number lookup results. |
| Invoice content | Missing required fields, incorrect tax rates, incorrect total amounts, or incorrect relationships between indicators. | Compare each item with the original document and the software's rules. |
| Digital signature | The digital certificate has expired, is invalid, or the signing date is incorrect. | Check the certificate expiration date, signing device, and system time. |
| Technical data | XML has incorrect structure, incorrect data types, duplicate numbers, or transmission/reception errors. | Open the transmission log and read the error code in the response message. |
| Invoice usage status | The account or authorization to use the invoice with the code is currently suspended. | Check the tax authority's notification and the registration status. |
If the error is related to your account or permissions, please follow the instructions. Unlock locked e-invoice account before sending it back.
How to handle electronic invoices that have been rejected for code issuance.
The safe approach is to proceed from feedback evidence to source data, avoiding deleting records or creating a new batch of invoices without knowing the cause. The goal is to correct the error correctly, avoid duplicate numbers, and maintain a trace of control.
- Save the error message before proceeding: Record the electronic transaction code, sending time, symbol, invoice number, reason for not issuing the code, and a screenshot of the status. This data is essential when working with suppliers or tax authorities.
- Identify the error class: Divide the problem into business data, registration information, digital signatures, technical structure, or connection interruptions. Do not modify multiple groups at once as it will be difficult to identify the root cause.
- Verify the source documents: For errors related to tax identification number, tax rate, tax amount, total amount, or date of creation, the contract, record, order, and tax configuration must be checked before making corrections.
- Correct the rejected field: Keep all unrelated data as is. In case of TVAN/KNTT errors or transmission unit information issues, compare the connection configuration with the electronic invoice registration file.
- Sign and send back: Only resend after the digital certificate is valid and the error has been resolved. Monitor the new response instead of assuming a successful submission means the code has been issued.
- Post-audit: Verify the tax authority code, lookup status, and final XML/PDF file before sending it to the buyer or incorporating it into the declaration process.
Handling common situations
The rejection message only indicates the outcome; the decision on how to proceed must be based on the type of error and its impact. The table below helps accountants differentiate between data correction, configuration modification, and system waiting.
| Token | Reasons for prioritizing inspection | Act | Evidence needs to be preserved. |
|---|---|---|---|
| One invoice was faulty, but the others were still issued with codes. | Buyer data, tax rate, total amount, required fields | Compare with the source documents, correct the fields, and resubmit. | Error messages and pre-/post-fix data |
| Multiple invoices with the same error in a short period of time. | Digital signature, pattern/symbol configuration, TVAN/KNTT, or connection. | Pause bulk sending, check configuration, and contact the receiving/transmitting unit. | List of transactions, timestamps, and common error codes. |
| Duplicate number notification or incorrect number sequence | Numbering rules, multiple simultaneous releases | Lock down parallel operations and compare logs before generating the next number. | User logs and generated number sequences |
| Signed but no response issued. | Unsent message, queue error, or system interruption. | Check the transmission and reception status; do not create a new copy just because the code is not yet visible. | Transaction code and queue status |
| The tax authority announces the suspension/temporary suspension of use. | Invoice registration status or terms of use | Address the root cause of the issue first; you can refer to the guide on unlocking a locked e-invoice account. | Tax authority notification and corrective action record |
After receiving the code, you should perform an independent verification step according to the instructions. Look up electronic invoices on the tax authority's system. before sending the final version to the client.
If an invoice is rejected for a tax code, do I still need to declare it or fill out form 04/SS-HĐĐT?
Invoices that are coded but not yet officially assigned a code should not be used as valid invoices for declaration purposes. Form 04/SS-HĐĐT, as per Appendix III of Circular 91/2026/TT-BTC, is a notification form for electronic invoices. It was created incorrectly.; Article 10 of this Circular defines that group as including invoices that have been assigned a code and invoices without a code that have submitted data to the tax authority. Therefore, Form 04 should not be automatically created simply because of a message indicating a refusal to assign a code.
How to prevent code denial errors
The most effective prevention is to control data before digital signing and monitor feedback after submission. Businesses should standardize customer lists, tax configurations, templates, symbols, digital certificates, and approval processes.
- Synchronize the seller's legal information with their electronic invoice registration profile.
- Verify the tax identification number and required data fields before issuing.
- Set up alerts when digital certificates are about to expire or during unusual signing times.
- Record the transmission logs for quick error code lookup.
- Clearly define the roles of creator, reviewer, and signatory.
For a broader review of operational errors, please refer to the following article. Common errors when using electronic invoices and how to fix them..
At what stage of the process can Bizzi assist?
In situations where invoice issuance is rejected, B-Invoice is suitable for assisting businesses in creating and managing electronic invoices in a unified process. According to Bizzi's feature documentation, B-Invoice supports creating invoices in XML/PDF format, connecting with the tax authority's system for verification, searching by invoice number, issue date, customer or tax code, downloading XML/PDF files, and tracking invoice status.
These features help accountants find the correct invoice to process, check its status after resubmission, and save the final XML/PDF version. B-Invoice is not described as a mechanism guaranteeing that invoices will always be assigned a code; the outcome depends on input data, digital signatures, registration information, and feedback from the tax authority's system.
- Before sending: Generate invoices using XML/PDF structure and verify source data according to business procedures.
- When processing is needed: Look up the correct invoice by number, date, customer or tax identification number and compare it with the notification from the tax authority.
- After resending: Track invoice status, download XML/PDF files, and save the processed version of the record.
Businesses can find more information about B-Invoice electronic invoice solution After determining the publishing, searching, and connection needs that are compatible with the existing system.
Frequently asked questions
The questions below focus on GSC queries and the accounting decisions that often need to be made immediately upon receiving error messages.
Are invoices that haven't been assigned a tax authority code valid?
For invoices that require a code, the uncoded version has not completed the issuance process and should not be sent to the buyer or used for declaration purposes.
If an invoice is rejected for a verification code, should it be canceled?
The invoice will not be automatically canceled. First, you need to read Form 01/TB-KTDL or the corresponding response, correct the reason for not issuing the code, and resubmit it. The process for handling incorrectly issued invoices will only be considered if the invoice falls within the scope of Article 10 of Circular 91/2026/TT-BTC.
What should I do if an invoice has been signed but not yet assigned a code?
Verify that the message has actually been sent or is still in the queue, then check the response regarding signature, data, and transmission channel. Do not immediately create new invoices without first determining the status of the old ones.
How do I handle a TVAN/KNTT information error where the information doesn't match the registration information?
Verify the transmitting and receiving units, connection methods, and information registered with the tax authorities; update the configuration correctly before resending. If multiple invoices have the same error, stop sending them in bulk to avoid creating further faulty transactions.
Does forgetting to submit invoices to the tax authorities for code issuance result in having the code issuance rejected?
No. "Forgot to send" or message still in the queue indicates an incomplete transmission/reception operation; "rejected" means a check response indicated ineligibility for code issuance. The status needs to be determined before choosing a course of action.
Will I be penalized immediately if my invoice is rejected for a code?
A notification of ineligibility for a code is not sufficient in itself to determine the penalty. The risk depends on subsequent actions, the timing of invoice creation/delivery, and whether the business uses an invalid invoice. Cases with a risk of delayed invoice creation or delivery should be reviewed according to current penalty regulations and actual records.
