If you plan to work or file taxes in Ontario, you need a Social Insurance Number (SIN). It’s your 9-digit federal ID for jobs and benefits. The fastest way is online; in-person works if you want a same-day paper letter. Below, you’ll see who actually needs a SIN, what to bring, realistic timelines, and plain-English rules on when not to hand it over.
When I helped my cousin apply last month, we did it online before breakfast. Their number showed up in My Service Canada Account a few days later. No drama.
Who actually needs a SIN (and when)
You’ll need a SIN once you’re hired (not for the application itself) and for things like bank interest reporting at tax time. Citizens, PRs, and eligible temporary residents all get one; temporary residents receive a 9-series SIN that expires with their permit. Yes, you can start working while you’re waiting—as long as you’re eligible to work. Just give the number to your employer promptly after you receive it.
Online vs in-person: pick one
Let’s keep it real. There is a mail option, but honestly, skip it unless you have no choice.
- Online: Upload clear photos/scans. Most people see their SIN appear in My Service Canada Account within about a week.
- In person: Bring your originals to a Service Canada Centre and, if everything’s fine, you walk out with the printed confirmation letter the same day.
Cost: Free. Applying, replacing, confirming—no fees.
What to bring (originals, not photocopies)
- Citizens: Birth certificate or Canadian citizenship certificate. If your current name doesn’t match, bring the name-change document.
- Permanent residents: PR card; or COPR plus foreign passport (usually fine soon after landing). Bring name-change proof if needed.
- Temporary residents (workers/students): A valid work permit or a study permit that clearly says you may work / may accept employment. If your study permit doesn’t say that, get it amended first. Your 9-series SIN will have an expiry date.
Pro tip from someone who’s been to way too many Service Canada offices: downtown Toronto locations (think Yonge Street) are a zoo at lunch. If you’re in Mississauga (Square One) or Brampton, expect lines. Go right at opening—or around 2–3 PM.
Quick steps (no fluff)
- Choose your route: online (quick) or in-person (same-day letter).
- Gather originals: status/ID document, plus any name-change proof. Keep a local proof of address handy if they ask.
- Apply: submit online or visit the centre.
- Get the number: online shows up in MSCA within roughly a week; in-person prints immediately.
- Tell the right people: your employer (after you’re hired) and your bank when needed for tax reporting.
- Lock it down: store the letter safely; don’t carry it daily.
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When not to share your SIN (and what to say)
Your SIN is not a general ID. Don’t hand it over for job applications, rental forms, phone/internet sign-ups, school admissions, or medical paperwork. If someone pushes, keep it simple:
“I don’t give out my SIN for that. Here’s my driver’s licence (or passport) instead.”
If a business insists where it isn’t required, ask for a supervisor. Still stuck? You can contact the federal privacy office for guidance.
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Employers, banks, and that “3-day” thing
Employers should ask for your SIN after you’re hired and within a few days of your start date. You can start work while your application is in progress. Once you receive the number, give it to payroll promptly (the usual expectation is within three days of receiving it). Banks will ask for your SIN only when they need it for tax reporting (think interest/dividends). If a payer doesn’t make a reasonable effort to collect a required SIN, the CRA can levy a small penalty—so they will follow up.
A quick story (real life, not “a mini case”)
My friend Sarah started at a café in November and panicked because her SIN wasn’t ready yet. Her manager said, “No problem—get it and send it over.” She applied online that afternoon, saw the number in her account within a week, emailed payroll, and that was that. Zero issues.
Scam-proof your SIN
Government agencies won’t text or call threatening to “suspend” your SIN. Don’t send your number by text or DMs. If something feels off, look up the agency’s phone number on its official site and call them yourself. Suspect fraud or identity theft? Call your local police, the Canadian Anti-Fraud Centre, and Service Canada’s SIN line for next steps.
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Small but important reminders
- SIN cards don’t exist anymore. You’ll get a paper confirmation letter (and you can view/print in your online account).
- If your status changes (permit extension, new PR card), update your SIN details so the expiry stays current.
- Keep copies of what you submitted. If you go in person, bring a charged phone—screenshots of permits and your online account sign-in can save time.
