Yes, you can file your Canadian tax return when your SIN has expired. A 900-series Social Insurance Number stays valid as a tax identifier with the Canada Revenue Agency even after the expiry date on your work or study permit has passed, so the CRA will still accept and process your return using that number. If you earned income in Canada, filing on time is what protects your refund and your benefit eligibility, and it should not wait on a SIN renewal.
Why an Expired SIN Still Works at the CRA
SINs beginning with 9 are issued to temporary residents and carry the same expiry date as the permit they are tied to.1Government of Canada. Social Insurance Number for Temporary Residents in Canada But the number itself is a tax identifier assigned under section 237 of the Income Tax Act, and it stays attached to your tax record permanently.2Canada.ca. Social Insurance Number (SIN) The CRA uses it to match the income your employer reported, the tax that was withheld from your paycheques, and any refund or credit you are owed.
The tax system runs on its own track from immigration enforcement. An expired permit does not erase the year’s earnings or the deductions your employer already remitted, and it does not disqualify you from filing.
How to File When Your SIN Is Expired
Enter your expired 900-series number on the return exactly as it appears. It is still your number. Paper filing is the most reliable route if you have not yet renewed, because it avoids any validation quirks on the electronic side.
NETFILE and commercial tax software may accept the expired SIN, since the number remains active in the CRA’s records, but some programs flag the expiry or refuse to transmit. If that happens, switch to a paper return rather than miss the deadline. If you cannot get a SIN at all before filing, the CRA allows you to send a paper return without one, together with a cover letter explaining the situation and a certified copy of your identity document.2Canada.ca. Social Insurance Number (SIN)
Deadlines Do Not Move Because Your SIN Expired
For the 2025 tax year, most individuals must file by April 30, 2026. Self-employed filers and their spouses have until June 15, 2026, but any balance owing is still due April 30, 2026 to avoid interest.3Canada.ca. Due Dates and Payment Dates
Late filing with a balance owing triggers a penalty of 5% of the unpaid amount, plus 1% for each full month the return is late, up to 12 months.4Canada Revenue Agency. Interest and Penalties on Late Taxes Interest on overdue amounts is charged at a prescribed rate, set at 7% for the first quarter of 2026.5Canada.ca. Interest Rates for the First Calendar Quarter An expired SIN buys no extension.
If You Are Working Under Maintained Status
If you applied to extend your permit before it expired, you have maintained status. You can keep working under the conditions of the expired permit until IRCC decides on your application.1Government of Canada. Social Insurance Number for Temporary Residents in Canada This authority sits in the Immigration and Refugee Protection Regulations.6Justice Laws Website. Immigration and Refugee Protection Regulations SOR 2002-227 – Section 186
For tax purposes, the income you earn during maintained status is ordinary employment income. Your employer should continue running normal payroll deductions for income tax, CPP, and EI even while your SIN reads as expired.7Canada.ca. Get the Social Insurance Number (SIN) From the Individual Those remittances get credited to your CRA account when you file.
Watch Out for Blocked Online Access and Paused Benefits
An expired SIN can lock you out of the CRA’s My Account portal. The Government of Canada directs temporary residents in this situation to the specific guidance for expired temporary SINs rather than to standard online services.8Government of Canada. Social Insurance Number – Overview Until your online access is restored, calling the CRA directly is the reliable way to confirm they have your current information.
Benefit payments can also stall. If the CRA cannot validate your file, deposits for programs like the Canada Child Benefit or the GST/HST credit may pause.9Canada Revenue Agency. Canada Child Benefit (CCB) – Keep Getting Your Payments People sometimes file successfully and then notice their benefits have gone quiet a month or two later. Updating your SIN and telling the CRA about any change in residency or personal details usually clears the block, and missed payments are typically issued on the next scheduled deposit once your entitlement is recalculated.
Renewing Your SIN After You File
Renewal is not a prerequisite for filing, but you will want an updated SIN for employment, benefits, and future tax years. Applying is free.10Government of Canada. Social Insurance Number Application
What You Need
Bring a primary document that proves both your identity and your status in Canada. For temporary residents, that is your current work permit, study permit, or visitor record, not a passport.11Employment and Social Development Canada. Social Insurance Number – Required Documents You will also need a secondary identity document, such as a passport or driver’s license. If your legal name differs from the name on your primary document, add a supporting document showing the change.
Where to Apply
Service Canada offers three channels:
- Online: upload digital copies through the Service Canada portal. Processing takes about 5 business days, with a confirmation letter mailed after.12Canada.ca. Contact the Social Insurance Number (SIN) Program
- In person: visit a Service Canada Centre with your original documents and receive your SIN at the appointment.10Government of Canada. Social Insurance Number Application
- By mail: send form NAS2120 with your original documents to the Social Insurance Registration Office in Bathurst, New Brunswick. Processing runs about 20 business days.13Canada.ca. Eligible to Apply for a SIN by Mail
Online and in-person applicants do not need to complete NAS2120; the process is handled digitally or by the Service Canada agent.14Government of Canada. Application for a Social Insurance Number – NAS2120 You will get a Confirmation of SIN letter with the new expiry date once processing is done.
Give the New Confirmation to Your Employer
Employers must verify that the immigration document authorizing work has not expired and, if it has, ask the employee to contact IRCC for a valid document.7Canada.ca. Get the Social Insurance Number (SIN) From the Individual They are still required to run payroll deductions in the meantime. Once your renewed SIN confirmation arrives, pass a copy to payroll so their records match yours.
File on time with the number you have. Renewing the SIN is a separate task, and treating it as a prerequisite is how people end up late, penalized, and waiting on benefits that could have kept flowing.