Mexican Código Postal Regex for Python

What this pattern does

This page provides a lightweight, single-purpose regular expression for matching mexican código postal, 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

# Mexican Código Postal
# ReDoS-safe | RegexVault — Localization > Postal Codes

import re

mexican_cdigo_postal_pattern = re.compile(r'^(0[1-9]|[1-9][0-9])[0-9]{3}$')

def validate_mexican_cdigo_postal(value: str) -> bool:
    return bool(mexican_cdigo_postal_pattern.fullmatch(value))

# Example
print(validate_mexican_cdigo_postal("06600"))  # True

Test Cases

When to use this pattern

This pattern is drawn from the Localization > Postal Codes 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

Mexican postal codes: 01000-16999 (Mexico City/CDMX), 36000-38999 (Guanajuato), 64000-67999 (Nuevo León), 97000-97999 (Yucatán). 00000 is reserved/invalid. SEPOMEX manages the Mexican postal database.