Canadian Transit Number Regex for JavaScript

What this pattern does

This page provides a lightweight, single-purpose regular expression for matching canadian transit number, ported and verified for JavaScript. 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 JavaScript project — whether you're validating in an Express middleware, a Next.js API route, or a client-side form.

Javascript Implementation

// Canadian Transit Number
// ReDoS-safe | RegexVault — Finance > Bank Identifiers

const canadianTransitNumberRegex = /^[0-9]{5}-?[0-9]{3}$/;

function validateCanadianTransitNumber(input: string): boolean {
  return canadianTransitNumberRegex.test(input);
}

// Example
console.log(validateCanadianTransitNumber("10000-002")); // 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 JavaScript developers because especially critical in long-running Node.js event loops where a ReDoS vulnerability can block the entire process. 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

Transit number format: BBBBBIII where BBBBB is branch number and III is institution number (002=TD, 003=RBC, 004=Scotiabank, 006=NBC, 010=CIBC, 016=HSBC, 219=ATB). Used with 7-12 digit account number.