Financial Year (FY2024 / FY2024-25) Regex for Python

What this pattern does

This page provides a lightweight, single-purpose regular expression for matching financial year (fy2024 / fy2024-25), 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

# Financial Year (FY2024 / FY2024-25)
# ReDoS-safe | RegexVault — Finance > Financial Formats

import re

financial_year_fy2024_fy202425_pattern = re.compile(r'^FY[0-9]{4}(?:[/-][0-9]{2})?$')

def validate_financial_year_fy2024_fy202425(value: str) -> bool:
    return bool(financial_year_fy2024_fy202425_pattern.fullmatch(value))

# Example
print(validate_financial_year_fy2024_fy202425("FY2024"))  # True

Test Cases

When to use this pattern

This pattern is drawn from the Finance > Financial Formats 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

Capture group 1: fiscal year start, group 2: end year (short or long form). Straddling years (FY2024-25 = April 2024 to March 2025) are common in UK, India, and Australia.