Each individual may use only one tax code. If a foreigner has been issued two personal tax codes (often after switching from the 9-digit ID to the 12-digit citizen ID, or when a new employer registers an additional code), the solution is to keep the earlier-issued code and terminate the later one. The current legal framework is Articles 10 and 11 of the Law on Tax Administration 108/2025/QH15 (effective 01/07/2026, replacing the Law on Tax Administration 38/2019/QH15), together with Circular 90/2026/TT-BTC guiding tax registration. Under Article 11 of Law 108/2025, an individual’s tax code is their personal identification number; the mechanism of using the personal identification number as the tax code has operated since 01/07/2025, with the tax authority automatically consolidating duplicate codes into a single identification number.
1. Why would one person have two tax codes?
Common causes: switching from the 9-digit ID card to the 12-digit citizen ID while a new payer registers a fresh code; registering at two different tax offices; or duplicated personal data. Foreigners may also get a new code when changing passports without updating their records.
2. Which code to keep and which to cancel?
Keep the earlier-issued tax code for declaration, withholding and PIT settlement; terminate the later-issued one. If the retained code is not yet linked to the new citizen ID or passport number, also file a change of tax registration information.
3. How do I terminate the second tax code?
Submit a written request to terminate the tax code (Form 24/DKT, issued with Circular 90/2026/TT-BTC) to the tax office that issued the second code. The dossier includes: an explanatory letter stating why there are two codes, a copy of the citizen ID or passport, and documents relating to both codes. After receiving the termination notice, look the code up again to confirm.
4. What changes with the personal ID number replacing tax codes from 01/07/2025?
Under Article 11 of the Law on Tax Administration 108/2025/QH15, an individual’s tax code is their personal identification number (the 12-digit citizen ID number) — a mechanism in place since 01/07/2025 and now guided by Circular 90/2026/TT-BTC (which replaced Circular 86/2024/TT-BTC from 01/07/2026); the tax authority automatically consolidates duplicate tax codes into one identification number. However, if a lookup still shows two active codes, the taxpayer should proactively terminate the redundant one to avoid settlement problems.
5. Is there a penalty for not consolidating?
There is no specific fine for holding two tax codes, but using two codes in parallel corrupts withholding, settlement and dependent data, which can lead to additional tax assessments or delayed refunds. Consolidate early.
This article provides general legal information and does not substitute advice for specific cases.
This article has been quality-reviewed by the FLAW AI Legal Council