Singapore Unique Entity Number (UEN) Validator
Validate the authenticity, format, and checksum of Singapore Unique Entity Number (UEN).
About Singapore Unique Entity Number (UEN) Validation
The validator verifies the three official Singapore UEN formats: ACRA businesses (9 digits `NNNNNNNNX`), local companies (10 characters `YYYYNNNNNX`), and other registered entities (10 characters `TYYPQNNNNX`).
Ensures entity type codes and checksum letters strictly match official Singapore government validation rules.
Anatomy & Structure of UEN — Singapore
The Singapore Unique Entity Number consists of 9 or 10 characters in 3 formats:
| Position | Field | Length | Meaning & Rule | Example |
|---|---|---|---|---|
| 1 to 4 | Incorporation Year | 4 digits | Year of incorporation for ACRA companies (Format A) | 2008 |
| 5 to 9 | Sequential / Entity Type | 5 digits/letters | Sequential corporate registration number | 12345 |
| 10 | Check Letter | 1 letter | Calculated via weighted Modulo 11 check algorithm by ACRA | M |
Official Algorithm (ACRA UEN Modulo 11)
Validation rules for Singapore UEN:
Structural validation (Formats A, B, C) + Weighted check letter calculation
- 1. Identify format: A (ACRA Companies), B (Sole Proprietors), or C (Other Entities).
- 2. Multiply characters by specific ACRA positional weights.
- 3. Map remainder to corresponding alphabetic check letter.