Canada 🇨🇦 · SIN

SIN name change after marriage — the 10-minute version

The SIN record is the anchor every other Canadian update checks against. Here is exactly what Service Canada wants, and why this comes before your licence and health card.

  1. 1. Gather two documents

    Government marriage certificate + valid photo ID. No SIN card needed — the number stays the same.

  2. 2. Go to any Service Canada Centre (or apply online)

    In person is processed immediately and free. By mail is possible but slow — only use it if no Centre is reachable.

  3. 3. Wait ~48 hours

    The record propagates to CRA-facing systems. Then update your driver's licence, health card, and finally tell payroll.

  4. 4. Tell your employer after

    Payroll must match the SIN record — the letter in our Canada kit words this for HR so nothing bounces.

Questions people actually ask

Can I change my SIN name online?
Partially. You can apply online through the SIN portal if you have valid digital copies of your documents, but the fastest and surest route is in person at any Service Canada Centre — the update is typically processed on the spot, free.
What documents do I need?
Your government-issued marriage certificate (from provincial Vital Statistics — not the ceremony record) and a valid photo ID. If your current SIN record is under your birth name, that's all a marriage name change needs.
Does my SIN number change?
Never. Only the name attached to the record changes. Anyone asking you to type your SIN into a website to 'process' a name change is a red flag — Service Canada handles it directly, for free.
Why does the SIN come first?
Payroll and CRA validate against your SIN record. Update it first, wait a couple of days, then do your licence and health card — otherwise you risk a T4 name mismatch in February.

The SIN is step 2 of 8.

The Canada Name Change Kit sequences all eight for your province — licence office, health card, CRA, passport — and writes the bank and employer letters for you. The checklist itself is free.

Canada guide · document-preparation aid, not legal advice.