EU European Health Insurance Card (EHIC) Number Regex for PHP

What this pattern does

This page provides a lightweight, single-purpose regular expression for matching eu european health insurance card (ehic) number, 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
// EU European Health Insurance Card (EHIC) Number
// ReDoS-safe | RegexVault — Identity & PII > Health Identifiers

define('EU_EUROPEAN_HEALTH_INSURANCE_CARD_EHIC_NUMBER_PATTERN', '/^[A-Z0-9]{8,20}$/');

function validate_eu_european_health_insurance_card_ehic_number(string $input): bool {
    return (bool) preg_match(EU_EUROPEAN_HEALTH_INSURANCE_CARD_EHIC_NUMBER_PATTERN, $input);
}

// Example
var_dump(validate_eu_european_health_insurance_card_ehic_number("12345678")); // bool(true)

Test Cases

When to use this pattern

This pattern is drawn from the Identity & PII > Health Identifiers 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

EHIC personal identification numbers vary significantly by issuing country. The card itself contains: country code, personal identification number, card number, and expiry date. Use country-specific patterns when the issuing country is known. UK issued the Global Health Insurance Card (GHIC) post-Brexit.