How To Handle An Employee With Two Personal Tax Codes

Key takeaways

• Starting July 1, 2025, the Personal Identification Number (PIN) will officially replace the Tax Identification Number (TIN), completely ending the issue of individuals having multiple tax IDs.
• Tax authorities will automatically merge all duplicate TINs into a single, unique PIN without requiring separate cancellation procedures.
• Before July 1, 2025, individuals with two TINs were required to submit Form 24/ĐK-TCT to cancel the later-issued TIN — either online via thuedientu.gdt.gov.vn or directly at the tax authority.
• All records, vouchers, and invoices that used an old TIN remain legally valid and do not need to be updated.
• Businesses must immediately review their HR data and update their software systems to comply with the new regulation.

If an individual has two TINs, the resolution process depends on when the issue arose — before or after July 1, 2025. From July 1, 2025, under Circular 86/2024/TT-BTC, tax authorities automatically merge all duplicate TINs into a single PIN (12-digit Citizen ID) — no manual cancellation required. Prior to this date, individuals had to proactively submit Form 24/ĐK-TCT to terminate the later-issued TIN.

Having two personal TINs typically occurs due to a switch from an old ID card (CMND) to a new Citizen ID Card (CCCD), registration with multiple employers, or duplicate CCCD numbers across provinces. The article below provides step-by-step guidance for each scenario to help businesses and employees comply with current regulations.

How duplicate tax IDs will be handled during the transition to PINs

Resolving duplicate TINs will be handled automatically through a modern technology system, completely removing the complex administrative procedures of the past.

Tax authorities require taxpayers to update their PIN for all TINs issued to them before July 1, 2025, including any duplicates. It is critical that taxpayers proactively review all tax numbers they have ever been issued and ensure their information is updated completely.

Once the update is complete, the system will automatically cross-reference the information with the National Population Database and proceed to merge all tax information, obligations, and transaction histories into the single, unique PIN. This process is fully automated and requires no manual intervention from the taxpayer.

Old, duplicate, or redundant TINs will be marked as “merged” in the system and will no longer be active. Notably, taxpayers do not need to file any separate cancellation procedures for these old tax numbers. All benefits, tax data, and obligation histories will be fully transferred to the new PIN.

In cases where identification information is not yet synced or has discrepancies with the population database, taxpayers must follow the procedure to update and supplement their personal records as outlined in Article 25 of Circular 86/2024/TT-BTC. Tax authorities will only merge the data and officially use the PIN as the new tax identifier after ensuring the information is a perfect match.

The legal status of old documents

One of the biggest concerns for businesses is the legal validity of past transactions that used an old TIN.

According to Clause 4, Article 39 of Circular 86/2024/TT-BTC, all records, vouchers, and invoices that were created or used an old TIN before July 1, 2025, will remain legally valid. Businesses are not required to adjust the information on these completed transactions to reflect the new PIN.

This means all employment contracts, payrolls, tax reports, and personal income tax deduction invoices that used an old TIN continue to be legally effective. Businesses can confidently use these documents for audits, cross-referencing, or resolving any future tax-related issues.

However, for all new transactions that occur on or after July 1, 2025, businesses must use the PIN as the tax identifier to ensure legality and avoid compliance risks.

How To Handle An Employee With Two Personal Tax Codes

The table below compares how to handle duplicate TINs before and after July 1, 2025:

If your Citizen ID information does not yet match the population database, follow these steps:

1. Look up your TIN at gdt.gov.vn or via the eTaxMobile/iCanhan app using your Citizen ID number
2. Check how many TINs are currently linked to your Citizen ID
3. If information does not match: Submit an update request at the tax authority or via the e-Tax Portal under Article 25 of Circular 86/2024/TT-BTC
4. Once information matches: The system will automatically merge — no further action needed

The Deputy Director General of the General Department of Taxation, Mai Son, emphasized that completing the tax registration process under Circular 86/2024/TT-BTC is a top administrative reform priority — synchronizing tax data with the national population database and eliminating all manual procedures for canceling duplicate TINs for individuals and businesses.

Frequently asked questions (FAQ)

Businesses often have many questions when dealing with duplicate TINs and the transition to the PIN system.

What are the common causes of duplicate tax IDs?

The issue of duplicate tax IDs typically stems from the following main causes:

• Changes in personal documents: When switching from a 9-digit CMND to a 12-digit CCCD, if an individual registers a new TIN without declaring their existing one, the system will issue a second TIN.
• Registration with multiple employers: Employees working at multiple companies, each registering a different TIN, leading to duplication.
• Duplicate CCCD numbers across provinces: Two different individuals share the same CMND/CCCD number due to an issuance error in different provinces, causing the tax system to record a shared TIN or issue one incorrectly.
• Unauthorized use: An individual’s or organization’s ID card number is used by someone else to register a TIN without the owner’s consent.

How can I check for my personal tax ID online?

Use your ID card number (CMND/CCCD) to search on the General Department of Taxation’s e-portal (gdt.gov.vn), the e-Tax Portal (thuedientu.gdt.gov.vn), or mobile apps like iCanhan and eTaxMobile. If the search results show more than one TIN, you need to update your information to have them merged into your single PIN.

Can I choose which tax ID to keep?

No, you cannot choose which TIN to keep. Under the new regulations effective July 1, 2025, all old TINs will be merged into a single, unique identifier: the 12-digit PIN on your Citizen Identity Card. This rule ensures consistency across the entire national tax management system.

What if the information on my old tax ID doesn’t match my citizen ID card?

You need to complete the procedure to change your tax registration information through the e-Tax Portal, the iCanhan or eTaxMobile app, or directly at a tax office to update it with the correct information from your Citizen ID Card. Once the updated information matches the National Population Database, your TIN will be synced with your PIN. This is also a key factor in effective HR systems integration.

Does my TIN match my Citizen ID number?

From July 1, 2025, the 12-digit Citizen ID number officially becomes the individual’s TIN under Circular 86/2024/TT-BTC — the two numbers are now identical. Prior to this date, TINs and Citizen ID numbers were separate codes, which was one of the main reasons individuals ended up with two TINs in the system.

What should I do if one TIN is managed by two different tax authorities?

This occurs when an employee registers a TIN at two different locations. From July 1, 2025, the system automatically merges everything into a single PIN, eliminating the situation where two authorities manage one TIN. If this issue is discovered, contact the tax authority where the second registration was made to transfer the records to a single managing authority before the system processes it automatically.

The transition to a PIN-based tax ID is a mandatory step in the government’s digitalization process. This is no longer just an administrative task to be handled—it is a systemic compliance requirement. Leaders should immediately direct their HR and accounting departments to conduct a comprehensive review and ensure their systems are compatible with the new regulation. Adapting early not only helps avoid the consequences of having two tax IDs but also affirms your company’s capacity for modern governance and legal compliance. To ensure this transition goes smoothly, businesses can consider a professional payroll service that is fully equipped to handle the latest legal requirements.