How to Apply for Old Age Security (Online or Form ISP-3550)
Most people are enrolled in OAS automatically and get a letter around their 64th birthday. If you get a letter asking you to apply, or none arrives within a month of turning 64, apply online in My Service Canada Account or by mailing Form ISP-3550. Online applications take about 14 days.
When you must use a paper form
- You live outside Canada. Send the form to the Service Canada office in the last province or territory you lived in.
- A power of attorney or trustee manages your OAS account.
- You are already receiving OAS.
Processing times
| How you applied | Allow |
|---|---|
| Online | 14 days |
| By mail | 120 days |
It takes longer if documents are missing or Service Canada needs more information. You'll get a decision letter by mail with your monthly amount and first payment date.
Want to start later?
You can delay OAS for up to 5 years for a bigger pension. In My Service Canada Account, choose Profile, then "Delay Receiving OAS/GIS Pension". Read should you delay OAS first.
Applying late
If you are past 65 and never started OAS, apply now. Service Canada may pay up to 11 months of back payments from the date it receives your application.
Helping someone apply
Form ISP-1603 lets someone talk to Service Canada for you, but not apply or change your payments. To manage OAS for someone who can't, a doctor completes Form ISP-3505, and the administrator signs Form ISP-3506.
Step by step
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Watch for your enrolment letter.
It arrives around your 64th birthday. If it says you are enrolled automatically and the details are right, you don't need to do anything.
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No letter a month after you turn 64? Contact Service Canada.
Call 1-800-277-9914 to find out if you need to apply.
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Gather your information.
Where you have lived since 18, your spouse's SIN and date of birth (if you have one), the date you want OAS to start, and your banking details for direct deposit.
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Apply online in My Service Canada Account.
Go to the Old Age Security section and choose "Apply for Old Age Security and manage my benefits". You can apply once you are at least 1 month past your 64th birthday.
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Or mail Form ISP-3550.
The Application for the OAS and the GIS. Include certified true copies of documents and sign in pen.
Phone numbers
CPP and OAS (also Personal Access Codes for returning CPP/OAS clients)
1-800-277-9914Agents: Monday to Friday, 8:30 am to 4:30 pm local time. Automated: 24/7.
From outside Canada and the U.S.: 1-613-957-1954 (collect, Eastern time)
TTY: 1-800-255-4786
Related
Frequently asked questions
Do I need to apply for OAS?
Most people don't. If Service Canada has your information, you are enrolled automatically and get a letter around your 64th birthday.
How early can I apply for OAS?
Online, once you are at least 1 month past your 64th birthday.
What if I disagree with the decision?
You have 90 days from the date you receive the decision letter to ask Service Canada to reconsider.
Sources
- Apply, delay, or change your start date (canada.ca, 2026-09-09) (canada.ca)
- After you apply (canada.ca, 2026-10-01) (canada.ca)
- When to start your pension (canada.ca)
North Help Desk is an independent guide, not a government website. Rules, amounts and phone hours can change; always confirm on the official page before you act. Spotted something out of date? Tell us.