Bank Account Number (Generic Sensitive) Regex for PHP

What this pattern does

This page provides a lightweight, single-purpose regular expression for matching bank account number (generic sensitive), ported and verified for PHP. 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 PHP project — whether you're validating in a Laravel validator, a WordPress plugin, or a standalone PHP script.

Php Implementation

<?php
// Bank Account Number (Generic Sensitive)
// ReDoS-safe | RegexVault — Identity & PII > Financial PII

define('BANK_ACCOUNT_NUMBER_GENERIC_SENSITIVE_PATTERN', '/^[0-9]{6,18}$/');

function validate_bank_account_number_generic_sensitive(string $input): bool {
    return (bool) preg_match(BANK_ACCOUNT_NUMBER_GENERIC_SENSITIVE_PATTERN, $input);
}

// Example
var_dump(validate_bank_account_number_generic_sensitive("123456")); // bool(true)

Test Cases

When to use this pattern

This pattern is drawn from the Identity & PII > Financial PII category and carries a ReDoS-safe certification. That matters for PHP developers because especially relevant in PHP where PCRE backtracking limits can trigger silent failures on malicious input. 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

Bank account numbers vary widely by country: UK 8 digits, US 5-17 digits, Singapore 9-12 digits, India 11-16 digits. This pattern covers the practical range. Always combine with routing/sort code for unambiguous bank identification.