US Passport Number Regex for Python

What this pattern does

This page provides a well-structured, multi-part regular expression for matching us passport number, ported and verified for Python. Identity and credential patterns need both correctness and safety, since they're frequent targets for adversarial input. 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

# US Passport Number
# ReDoS-safe | RegexVault — Identity & PII > Passport Numbers

import re

us_passport_number_pattern = re.compile(r'^[A-Z][0-9]{8}$|^[A-Z]{2}[0-9]{7}$')

def validate_us_passport_number(value: str) -> bool:
    return bool(us_passport_number_pattern.fullmatch(value))

# Example
print(validate_us_passport_number("A12345678"))  # True

Test Cases

When to use this pattern

This pattern is drawn from the Identity & PII > Passport 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

US passport books use 1 letter + 8 digits. US passport cards also use 9 alphanumeric characters. Older US passports may have different formats. The State Department does not publish the exact checksum algorithm.