Personal identification number replacing tax code from 1 July 2025: what businesses must do

From 1 July 2025, the personal identification number (PIN) replaces the tax code for individuals, dependents, households, household businesses and individual businesspersons — the most significant change in individual tax administration in many years. For businesses, as income payers, the impact is direct: from personal income tax (PIT) declaration and withholding, dependent registration, invoicing individual customers, to electronic tax transactions. This article summarizes the legal basis, the key changes, and a checklist of what businesses should do now.

Table of contents

• 1. Overview of the legal instruments
• 2. Key changes
• 3. Practical impact on businesses
• 4. Action items and timeline
• 5. Open points to monitor
• 6. Frequently asked questions

1. Overview of the legal instruments

Circular 90/2026/TT-BTC (Thông tư 90/2026/TT-BTC) (effective 1 July 2026, replacing Circular 90/2026/TT-BTC) of the Ministry of Finance governs tax registration. It is the central instrument implementing a policy set out earlier in Article 35(7) of the Law on Tax Administration 38/2019/QH14 (Luật Quản lý thuế 38/2019/QH14): "When personal identification numbers are issued to the entire population, the personal identification number shall be used in place of the tax code."

The effectiveness point to remember: Circular 86 took effect generally on 6 February 2025, but the rule on using the PIN in place of the tax code was "deferred" under Article 38(2) — tax codes issued by the tax authority to individuals, households and household businesses continued to be used through 30 June 2025; from 1 July 2025, taxpayers, tax administration authorities and relevant organizations and individuals use the personal identification number in place of the tax code.

Implementing this rule, the Department of Taxation issued two important guidance documents just before 1 July 2025: Official Letter 2065/CT-NVT (Công văn 2065/CT-NVT) dated 26 June 2025 on implementing the use of the personal identification number in place of the tax code and the use of organizations' electronic identification accounts in electronic tax transactions; and Official Letter 2163/CT-QLTT (Công văn 2163/CT-QLTT) dated 30 June 2025 guiding taxpayers on how to record the PIN in tax dossiers.

Conceptually, the personal identification number is a natural 12-digit number assigned by the National Population Database to each Vietnamese citizen, uniformly managed nationwide by the Ministry of Public Security and never duplicated between individuals (Article 12 of the Law on Identification 2023 (Luật Căn cước 2023)). In practice, it is the number printed on the chip-based citizen identity card.

2. Key changes

2.1. Who uses the PIN in place of the tax code — and who does not

Under Article 5(1)(b) and Article 5(5) of Circular 90/2026/TT-BTC, the personal identification number is used in place of the tax code of:

• individual taxpayers and dependents under PIT rules;
• households, household businesses and individual businesspersons — through the PIN of the household representative, the household business representative, or the individual businessperson.

By contrast, the following groups do not switch to the personal identification number:

• enterprises and organizations: they continue to use tax codes issued by the tax authority, unchanged;
• foreign nationals, or Vietnamese nationals residing abroad without a PIN established in the National Population Database: they continue to use the 10-digit tax code issued by the tax authority (Article 5(4)(a) of Circular 86).

The second exception matters particularly for FDI enterprises with foreign specialists — analyzed in section 3.

Comparison table — before and after 1 July 2025:

2.2. The transition: three cases under Article 39

Circular 86 does not require every taxpayer to file for a tax-code change. Article 39 provides transitional treatment in three cases:

Case 1 — data already matched with the National Population Database: the tax authority converts automatically, with no administrative procedure arising for the taxpayer. Household businesses, households and individuals use the PIN in place of the tax code from 1 July 2025, including for adjusting and supplementing tax obligations arising under previously issued tax codes. The tax authority manages all data — including family-deduction registration data of dependents — by the PIN.

Case 2 — data not yet matched or incomplete: the tax code is moved to status 10 — "tax code awaiting update of the personal identification number." The taxpayer must complete the tax-registration-information change procedure under Article 25(1) and (4) of Circular 86 so the data correctly matches the National Population Database before using the PIN in place of the tax code.

Case 3 — an individual holding more than one tax code: the taxpayer must update the PIN information for each issued tax code so the tax authority can integrate the tax codes into the PIN, consolidating the taxpayer's tax data under a single identifier. The upside: invoices, documents, tax dossiers and other legally valid papers already prepared with the old tax code continue to be used for tax administrative procedures and to evidence tax obligations — there is no need to change the tax code on them to the PIN.

2.3. How to record the PIN in tax dossiers

Official Letter 2163/CT-QLTT gives very practical guidance in its Section 3: once the PIN is used in place of the tax code, the taxpayer enters the personal identification number in the "tax code" field on returns, tax payment documents, invoices, PIT withholding dossiers and any other documents requiring a tax code. In other words, the form labels do not change — the content entered changes from the 10-digit tax code to the 12-digit PIN.

One point worth noting for the 2025 PIT finalization: where a tax code is in "awaiting update" status, the taxpayer may update information on eTax, and this does not affect the filing of the 2025 PIT finalization. Longer term, the tax system will link tax codes by PIN, net tax obligations by PIN, and consolidate nationwide PIT finalizations by the single PIN (Official Letter 2065/CT-NVT).

2.4. Organizations' electronic identification accounts in electronic tax transactions

Alongside the 1 July 2025 milestone comes a parallel change businesses must not miss: under Official Letter 2065/CT-NVT and Decree 69/2024/ND-CP (Nghị định 69/2024/ND-CP) on electronic identification and authentication, accounts issued to organizations by the National Public Service Portal may be used only through 30 June 2025. From 1 July 2025, individuals, organizations and enterprises use electronic identification accounts issued by the Ministry of Public Security for electronic tax administrative procedures.

When applying for an organization's electronic identification account, the business must declare information consistent with its enterprise registration and tax registration: the organization's name, tax code, date of establishment, head-office address; and the legal representative's full name and PIN. Exception: where, as of 1 July 2025, the application is in progress but the account has not yet been issued, or the individual is a foreign national / the organization has a foreign legal representative not yet issued an electronic identification account, the entity continues to perform state-budget obligations via the electronic tax account until the account is issued.

2.5. The direction set in the 2025 Law on Tax Administration

The Law on Tax Administration 108/2025/QH15 (Luật Quản lý thuế 108/2025/QH15) (effective 1 July 2026) reinforces this direction in Article 11(1): the tax code of individuals, households, household businesses and individual businesspersons is the personal identification number issued under the law on identification. The conversion from 1 July 2025 is therefore not a stopgap measure but a strategic, long-term legislative move. Businesses should build internal processes around the PIN as the single tax identifier for individuals, rather than treating this as a one-off update.

3. Practical impact on businesses

3.1. Businesses with Vietnamese employees

The most affected group. Every PIT-related operation for employees — monthly withholding, annual finalization, dependent registration and adjustment, issuance of withholding certificates — now uses the PIN in the tax-code field. Accounting systems, payroll software and filing tools (HTKK, eTax) must be updated to accept the 12-digit format instead of the old 10-digit one. The most common error is legacy systems still validating a 10-character length, causing returns to be rejected.

3.2. Businesses with foreign specialists and employees

This group needs separate handling — do not apply the rules mechanically. Foreign employees without a PIN continue to use the 10-digit tax code issued by the tax authority. In practice, many FDI enterprises have both groups on the same payroll and the same withholding return — HR and accounting must classify each individual correctly and never enter a passport number or a non-existent PIN in the tax-code field. Where the legal representative is a foreign national, also note the electronic-identification-account exception in section 2.4.

3.3. Businesses dealing with household businesses and individual businesspersons

When purchasing goods or services from a household business, or renting property from an individual, the enterprise — as buyer and withholding party — must update counterparty information: the household business's old tax code is replaced by the PIN of the household business representative. Ongoing contracts should be reviewed for tax-information clauses; PIT withholding documents (for example, 10% withholding on payments to individual businesspersons) must record the new PIN. E-invoices issued to individual customers likewise record the PIN in the tax-code field.

3.4. Risks of delayed updates

The risk is not a direct penalty for "failing to change the tax code" — the law imposes no such change procedure — but operational consequences: returns rejected by the system over format errors, mismatched withholding data blocking employees' PIT finalizations, and dependent information not recorded correctly, costing family deductions. For businesses, the biggest cost is usually the time spent reprocessing dossiers and explaining to employees when their tax benefits are affected.

4. Action items and timeline

Businesses should proceed in the following order of priority:

1. Check the tax-code status of every employee — look up on eTax Mobile or the electronic tax portal; list cases whose tax codes are in status 10 "awaiting personal identification number update" and work with employees to update tax registration information to match the National Population Database. Do this now, not at finalization time.
2. Classify foreign employees separately — keep a separate list of employees without a PIN, continue using the tax authority-issued tax code for them when filing, and double-check that no other identifier is entered in the tax-code field by mistake.
3. Update filing and payroll systems — reconfigure payroll software, HTKK/eTax and internal forms so the individual's tax-code field accepts the 12-digit PIN format; test character-length validation rules before filing official returns.
4. Review dependent registrations — for new family-deduction registrations, use the dependent's PIN; re-check previously registered dossiers so the tax authority manages the data uniformly under the PIN.
5. Update e-invoice templates and counterparty information — configure invoicing software to record the PIN in the tax-code field when the buyer is an individual; update the tax information of household-business and individual-businessperson suppliers in the counterparty master data.
6. Complete the organization's electronic identification account — reconcile registration data (name, tax code, establishment date, head-office address, legal representative information) between enterprise registration and the tax authority before applying; enterprises with a foreign legal representative should note the exception timeline and continue using the electronic tax account while waiting.
7. Archive and reconcile old dossiers — invoices, documents and tax dossiers already prepared with the old tax code remain legally valid and need not be amended; but when looking up or reconciling tax obligations later, use the PIN as the primary search key.

5. Open points to monitor

Alongside the well-guided content, there are points businesses should monitor rather than conclude hastily:

• Updating the PIN on eTax for individuals holding multiple tax codes: the law sets the principle of consolidating data under the PIN, and secondary guidance indicates information may be updated on eTax; however, the detailed step-by-step process for each specific case may continue to be refined by the tax authority. Businesses with employees in this situation should follow new guidance proactively and work early with their directly managing tax authority.
• The specific list of return templates affected: Official Letter 2163/CT-QLTT states the general principle — "enter the personal identification number in the tax-code field on returns" — without enumerating each template number. When filing taxes involving individuals, businesses should check against the latest template versions on the electronic tax system at the time of filing.
• Digital certificates and digital signatures of individuals: no verified regulation has yet been found mandating an update of digital certificates from the old tax code to the PIN. Businesses and individuals should check directly with their digital-signature certification service provider rather than drawing their own conclusions.

For specific situations arising during the transition — particularly involving foreign employees, dependents, or tax obligations of prior periods — businesses should seek legal advice before acting to avoid downstream risk.

6. Frequently asked questions

From 1 July 2025, must businesses file to convert employees' tax codes to the personal identification number?

No. Conversion is performed automatically by the tax authority on the system for cases where tax registration information already matches the National Population Database; no administrative procedure arises for taxpayers upon conversion (Article 39 of Circular 90/2026/TT-BTC). Businesses only need to check employees' tax-code status and coordinate information updates where the tax code is in "awaiting personal identification number update" status.

For PIT declarations for employees from 1 July 2025, should the old tax code or the personal identification number be entered?

Enter the PIN in the "tax code" field on returns, tax payment documents, PIT withholding dossiers and any documents requiring a tax code, per the guidance in Official Letter 2163/CT-QLTT of the Department of Taxation. Where the tax code is in "awaiting update" status, the taxpayer may update information on eTax; this does not affect the filing of the 2025 PIT finalization.

How are foreign employees without a personal identification number declared?

Individuals who are foreign nationals, or Vietnamese nationals residing abroad without a PIN established in the National Population Database, continue to use the 10-digit tax code issued by the tax authority (Article 5(4)(a) of Circular 90/2026/TT-BTC). Businesses must correctly classify these two employee groups when filing to avoid confusion.

What information goes on e-invoices issued to individual customers from 1 July 2025?

Record the PIN in the tax-code field on the invoice, per Official Letter 2163/CT-QLTT. Businesses should review invoice templates and configure e-invoicing software so the field accepts the 12-digit PIN format.

Do invoices and documents already prepared with the old tax code before 1 July 2025 remain valid?

Yes. Under Article 39(4) of Circular 90/2026/TT-BTC, once the tax code has been integrated into the PIN, invoices, documents, tax dossiers and other legally valid papers already prepared using the individual's tax code continue to be used for tax administrative procedures and to evidence tax obligations, without changing the tax code on them to the PIN.

Does your business need a review of its PIN conversion?

Switching to the personal identification number in place of the tax code looks simple, but it touches the entire HR — accounting — tax process of a business, especially for FDI enterprises with both Vietnamese employees and foreign specialists. FLAT Law Firm helps businesses check the tax-code status of employees, update PIT filing processes and e-invoicing, handle cases of data not yet matched with the National Population Database, and accompany them through electronic tax transactions using the organization's electronic identification account. Contact our hotline at 0988424851 for advice on your business's specific situation.

References

• Thông tư 90/2026/TT-BTC (Circular No. 90/2026/TT-BTC) (effective 1 July 2026, replacing Circular 90/2026/TT-BTC) of the Ministry of Finance on tax registration (effective February 6, 2025)
• Luật Quản lý thuế số 38/2019/QH14 (Law on Tax Administration No. 38/2019/QH14), Article 35(7)
• Công văn số 2065/CT-NVT (Official Letter No. 2065/CT-NVT) dated June 26, 2025 of the Department of Taxation on implementing the use of the personal identification number in place of the tax code
• Công văn số 2163/CT-QLTT (Official Letter No. 2163/CT-QLTT) dated June 30, 2025 of the Department of Taxation guiding taxpayers on using the personal identification number in place of the tax code
• Luật Căn cước số 26/2023/QH15 (Law on Identification No. 26/2023/QH15), Article 12
• Luật Quản lý thuế số 108/2025/QH15 (Law on Tax Administration No. 108/2025/QH15), Article 11(1) (effective July 1, 2026)
• Nghị định số 69/2024/ND-CP (Decree No. 69/2024/ND-CP) dated June 25, 2024 of the Government on electronic identification and authentication

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