Singapore Phone Number Regex for Python

What this pattern does

This page provides a well-structured, multi-part regular expression for matching singapore phone number, ported and verified for Python. A rigorously tested regex reduces debugging time and protects your application from edge-case failures. The snippet below is ready to drop into your Python project — whether you're validating in a Django view, a FastAPI endpoint, or a standalone data processing script.

Python Implementation

# Singapore Phone Number
# ReDoS-safe | RegexVault — Localization > Phone Numbers

import re

singapore_phone_number_pattern = re.compile(r'^(?:\+65\s?)?[3689][0-9]{3}\s?[0-9]{4}$')

def validate_singapore_phone_number(value: str) -> bool:
    return bool(singapore_phone_number_pattern.fullmatch(value))

# Example
print(validate_singapore_phone_number("+65 9123 4567"))  # True

Test Cases

When to use this pattern

This pattern is drawn from the Localization > Phone Numbers category and carries a ReDoS-safe certification. That matters for Python developers because particularly important in Python web servers where CPU-bound regex operations can stall concurrent request handling. RegexVault audits patterns against known backtracking attack vectors, ensuring you have the necessary context before using this regex in a high-stakes production environment.

Common Pitfalls

Technical Notes

Singapore number prefixes: 3 (VoIP/Internet calling), 6 (landline), 8 (mobile), 9 (mobile). All Singapore numbers are 8 digits. +65 is the country code. Emergency numbers (999, 995) do not follow this format.