OAS Calculator (Old Age Security)

How to Use the OAS Calculator

1. Choose your age group; OAS is 10% higher from age 75.
2. Enter the years you have lived in Canada after age 18; 40 years gives full OAS.
3. Pick the age you start OAS; each month of deferral adds 0.6%, up to age 70.
4. Enter your 2026 net world income to check the OAS clawback.
5. Read your estimated monthly OAS, yearly amount and any clawback.

Choose your age group, then enter the full years you have lived in Canada since your 18th birthday. Then pick the start age for your OAS pension, from 65 with no deferral up to 70.

Next, enter your expected net world income for 2026, which is line 23400 of your return including OAS itself. Tick the box if you live outside Canada, because the minimum residence rule is different there.

This old age security calculator then shows your estimated monthly pension, the yearly amount before and after any clawback, and your share of the full pension. A step table underneath then explains every single figure.

OAS Payment Amounts for October to December 2026

The maximum monthly OAS for October to December 2026 is $762.50 at ages 65 to 74. From age 75, the pension includes an automatic 10% increase, which then lifts the maximum to $838.75 a month.

OAS is indexed to the Consumer Price Index and reviewed quarterly, in January, April, July and October. Amounts usually rise slightly through the year when prices rise, and they are not reduced when prices fall.

The figures used here come from the Employment and Social Development Canada rates for October to December 2026, the latest published quarter. Later quarters will differ, so recheck the amounts whenever a new quarter begins.

How OAS Is Calculated

The OAS formula starts with the full pension for your age group. It then multiplies that by your residence fraction, adds any deferral increase, and applies the extra 10% if you are 75 or older.

The residence fraction is your full years in Canada after 18 divided by 40, capped at a maximum of one. The deferral factor adds 0.6% for each of the months deferred past your 65th birthday.

Multiplying the monthly result by 12 gives the yearly amount. The calculator then subtracts the recovery tax, which is 15% of net world income above $95,323, and it is never more than the pension itself.

Worked OAS Example

Take someone aged 67 who lived in Canada for 30 years after 18 and started OAS at 65. Their partial pension is $762.50 times 30/40, which comes to $571.88 a month or $6,862.50 a year.

If their 2026 net income is $120,000, the clawback is 15% of $120,000 minus $95,323. That is 15% of $24,677, or $3,701.55 of recovery tax for the whole year. Part may already be withheld monthly.

After the recovery tax, they keep $3,160.95 of OAS for the year. The calculator shows each of these steps in its table, so you can follow the arithmetic line by line and check it yourself.

Years in Canada and Partial OAS

A full pension needs 40 years of residence in Canada after age 18. With fewer years, you receive 1/40 of the full pension for each full year, so 25 years gives 62.5% of the maximum.

You need at least 10 years of residence after 18 to receive OAS while living in Canada, and at least 20 years to keep receiving it while you live abroad for more than six months.

Social security agreements between Canada and other countries can help you meet those minimum residence rules. The calculator does not model these agreements, so check directly with Service Canada if you lived or worked abroad.

Deferring OAS to Age 70

Each month of deferral after 65 raises your pension by 0.6% per month, or 7.2% a year. The increase stops at 36% at age 70, so waiting any longer than that adds nothing at all.

A full pension deferred to 70 pays $1,037.00 a month at current rates. Ignoring tax and indexing, the higher payment makes up the five missed years after about 14 years, a breakeven near age 84.

Deferral can often suit people still working, those facing a clawback before 70 or anyone expecting a long life. Unlike CPP, which can start at 60, OAS cannot begin before age 65 under any option.

The OAS Clawback Explained

The recovery tax applies when your individual net world income is above the clawback threshold, which is $95,323 for the 2026 income year. You then repay 15 cents of OAS for each dollar above it.

Service Canada usually withholds the expected recovery tax from monthly payments from July to June, based on income two years earlier. The final amount is settled on your tax return, so refunds or balances happen.

Here, a full pension at ages 65 to 74 is completely recovered at about $156,323. TFSA withdrawals do not count as net income, and pension income splitting between spouses can also lower the recovery tax.

GIS and Other Benefits

The Guaranteed Income Supplement is a monthly, income-tested benefit for low-income seniors who receive OAS. It is not taxable, and it stops at lower incomes than OAS, so it helps a different group of seniors.

For October to December 2026, a single senior can receive up to $1,138.90 a month in GIS with income under $23,112. Couples where both receive a full OAS pension can each get up to $685.56.

The separate Allowance helps some people aged 60 to 64 whose spouse receives OAS and GIS. This tool is not a full OAS and GIS calculator, so check the Canada.ca payment amounts for your situation.

Applying for OAS and Estimate Limits

Many people are enrolled automatically and receive a letter the month after they turn 64. If you do not get one, apply through My Service Canada Account, choosing any start month between 65 and 70.

If you already receive OAS, you can cancel within six months of the first payment and restart later, but you must repay what you received. The deferral then applies from the new start date instead.

This is an estimate. It uses full years only and does not model social security agreements, periods in prison or the exact withholding schedule. Service Canada sets your actual amount, which is indexed every quarter.

Frequently asked questions