UK Sort Code Regex for Python

What this pattern does

This page provides a well-structured, multi-part regular expression for matching uk sort code, ported and verified for Python. Financial data validation has zero tolerance for false negatives — a missed invalid entry can corrupt downstream calculations. 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

# UK Sort Code
# ReDoS-safe | RegexVault — Finance > Bank Identifiers

import re

uk_sort_code_pattern = re.compile(r'^(?:[0-9]{6}|[0-9]{2}-[0-9]{2}-[0-9]{2})$')

def validate_uk_sort_code(value: str) -> bool:
    return bool(uk_sort_code_pattern.fullmatch(value))

# Example
print(validate_uk_sort_code("60-16-13"))  # True

Test Cases

When to use this pattern

This pattern is drawn from the Finance > Bank Identifiers 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

Sort codes identify the bank and branch. The first two digits identify the bank (20=Barclays, 30=Lloyds, 40=HSBC, 60=NatWest). Normalize to 6 digits (strip hyphens) before storage.