Singapore Tax ID Number (TIN) Guide 

A Tax Identification Number (TIN) is a unique identifier assigned to taxpayers by the relevant tax authority for the purpose of tracking tax obligations and ensuring tax compliance. In Singapore, the TIN is an essential element for individuals, businesses, and legal entities in fulfilling their tax obligations. It is necessary for filing tax returns, applying for tax reliefs, and making various tax-related payments. 

This guide provides detailed and verified information about TINs in Singapore. All data has been sourced directly from official tax authority websites to ensure 100% accuracy and reliability. 

1. Tax Identification Number Types 

In Singapore, the Tax Identification Number (TIN) is known by the following names based on the type of taxpayer: 

• For Individuals: The TIN is commonly referred to as the “NRIC Number” (National Registration Identity Card number) for Singaporean citizens and permanent residents. This number is also used for tax purposes. 

• For Businesses: Businesses are assigned a unique “UEN” (Unique Entity Number) by the Accounting and Corporate Regulatory Authority (ACRA), which also serves as the TIN for tax-related matters. 

Key Points: 

• Individual TIN: NRIC Number for individuals (Singapore citizens and permanent residents). 

• Business TIN: UEN (Unique Entity Number) for registered businesses, including sole proprietorships, partnerships, and corporations. 

The official tax authority in Singapore, the Inland Revenue Authority of Singapore (IRAS), manages the issuance of TINs for both individuals and businesses. 

2. TIN Format and Structure 

Individual TIN (NRIC Number): 

• The NRIC number consists of 9 alphanumeric characters. 

• Structure: The first letter indicates the individual’s registration type (S for Singaporean citizens, F for foreign individuals with work passes, etc.), followed by a seven-digit unique identification number, and ends with a letter that serves as a checksum. 

Example: S1234567D (where “S” indicates the person is a Singaporean citizen, “1234567” is a unique identifier, and “D” is a checksum letter). 

Business TIN (UEN): 

• The UEN is a 9-10 digit alphanumeric identifier. 

• Structure: The first part of the UEN indicates the entity type (e.g., for companies, the number begins with the year of registration), followed by the registration number, and a checksum digit or letter. 

Example: 200000000W (where “200000000” is the registration number, and “W” is the checksum letter). 

Note: Both NRIC and UEN numbers do not include spaces or dashes. 

3. Issuing Authority and Registration Process 

• Tax Authority: The official authority responsible for issuing TINs in Singapore is the Inland Revenue Authority of Singapore (IRAS). 

• Official Website: www.iras.gov.sg 

Individual TIN Registration (NRIC Number) 

1. Eligibility: Singapore citizens and permanent residents automatically receive an NRIC when they reach the age of 15. 

2. Application: No separate application is required for NRIC. Upon turning 15, citizens and permanent residents are issued their NRIC number by the National Registration Office. 

3. Documents: Birth certificate, Singapore citizenship certificate, or permanent residency status documents. 

4. Fees: No fee is involved for registration. 

Business TIN Registration (UEN) 

1. Eligibility: Any business entity, including sole proprietorships, partnerships, and companies, must register for a UEN with ACRA. 

2. Application Process: Businesses can register for a UEN through the ACRA online portal. 

• Steps: 

• Visit ACRA’s BizFile Portal. 

• Complete the registration form with business details. 

• Upload necessary documents (e.g., business plan, director details). 

• Receive UEN upon successful registration. 

3. Documents: Business registration documents, personal identification of directors, proof of address, etc. 

4. Fees: A registration fee is applicable based on the type of business entity. 

For more details, visit the official ACRA website. 

4. TIN Verification and Lookup 

To verify TINs in Singapore: 

• For Individuals (NRIC Number): NRIC numbers can be validated via official government portals or through the SingPass system for individuals accessing government services. 

• For Businesses (UEN): Businesses can verify their UEN by using the official ACRA search service. 

• UEN Verification: Visit ACRA UEN Search Portal to check the validity of a UEN. 

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5. TIN and VAT Number Connection 

In Singapore, the UEN also serves as the GST (Goods and Services Tax) Number for businesses registered under the Goods and Services Tax Act. The UEN is used by businesses for all GST-related purposes, including issuing invoices, filing returns, and paying GST. 

GST Number Format: The GST Number is the same as the business’s UEN. The format and structure of the UEN apply equally to GST purposes. 

6. Why Accurate TIN Validation Matters 

Ensuring the accuracy of your TIN is critical for both businesses and individuals in Singapore. An incorrect or unverified TIN can lead to serious complications such as: 

• Delays in tax processing 

• Rejection of tax exemption claims 

• Fines and penalties for non-compliance 

• Rejection of e-invoicing submissions 

• Onboarding unqualified suppliers or customers 

• Data quality issues across finance and compliance systems 

Using the Singapore ACRA UEN Search Portal or TaxDo real-time global tax ID verification platform ensures accurate Tax ID validation, error reduction, and full compliance with Singapore tax laws. 

7. Stay Compliant with TaxDo 

While the ACRA UEN Search Portal offers a basic PIN checker, TaxDo takes Singapore TIN validation to the next level with real-time results, periodic revalidation for ongoing compliance, and seamless integration into your systems. 

With TaxDo, you can automate Tax ID validation, monitor changes, and ensure continuous compliance, all from a single, user-friendly dashboard or through API connectivity. 

TaxDo is trusted by leading enterprises, platforms, and compliance teams worldwide. Try it now and eliminate the risks of Tax ID errors in Singapore and beyond.