OAS Calculator

What the calculator estimates

This calculator estimates a monthly Old Age Security (OAS) pension before recovery tax and ordinary income tax.

If your OAS start age is later than your current age, it projects OAS at that start age using the annual payment growth assumption entered. Otherwise, it estimates OAS at your current age using the published payment amounts for the period shown.

For a current OAS estimate within the supported pension rules, you can also estimate GIS when In Canada is selected. GIS is not included in future OAS projections.

Calculation method

Qualifying residence years are completed years of Canadian residence after age 18 accumulated by the OAS start age entered. Add the relevant residence periods before taking the completed whole years. For a future start, use the years expected by then; for OAS already started, exclude residence accumulated afterward. A deferred-partial-pension comparison may use residence at an earlier eligibility point. Those calculated years do not replace the residence years entered at OAS start. This is a residence measure, not a count of years worked or contributed to CPP/QPP.

Once a partial OAS pension is approved, additional residence in Canada does not increase its approved residence proportion. Deferral and the increase at age 75 are separate adjustments.

For an ordinary residence-based amount before deferral and age-related adjustments:

M is the full monthly OAS reference amount for ages 65–74 in the payment period used; Y is the qualifying residence years entered. The residence proportion cannot exceed 40/40.

For an OAS start after age 65, the calculator derives ordinary eligibility timing from the start age, qualifying residence years at that age and where you live when receiving OAS. It compares the applicable residence-based and deferred-pension amounts and uses the greatest applicable amount. Age-related adjustments and any future payment-growth assumption are applied separately.

For a future start:

P (start) is the resolved starting monthly OAS estimate for the pension being illustrated; g is the annual growth assumption as a decimal; S is OAS start age; and C is current age. A 2% assumption is 0.02. Growth is applied once and does not add residence years, reapply deferral or duplicate an age-related increase.

A partial OAS pension does not automatically mean a lower combined OAS and GIS amount. For an ordinary partial pension, the GIS formula accounts for the difference between the full OAS pension for the person's age and their OAS pension before any increase for starting later. Income and the selected benefit situation still affect the result.

This calculator supports ordinary partial pensions established using 10 to 39 qualifying residence years. Pensions involving fewer than 10 Canadian residence years, special qualifying factors or an additional couple adjustment may need different treatment.

The partial-pension adjustment enters the benefit formula before the final income-tested amount is determined.

GIS is normally based on income from the standard income year for the payment period. After retirement or a reduction in pension income, Service Canada may use an estimated-income basis under its rules. The current-year option here is an illustration; it does not determine which income Service Canada will accept.

Illustrative example

Assume 34 completed qualifying residence years at OAS start, no deferral or age-75 increase, and a hypothetical full monthly OAS amount of $800, not a published payment rate.

The starting estimate is $680.00 per month. If you are 45 and plan to start OAS at 65, the start is 20 years away. With assumed annual payment growth of 2%:

The projected amount is $1,010.44 per month in future dollars. The 34 residence years are an entered assumption for pension start, not a number inferred from the projection horizon. The result illustrates the growth assumption; it is not a government forecast.

Suppose a full monthly OAS pension is $800 and a pension based on 20 qualifying years is $400. With no other income, assume the GIS amount for a full-OAS recipient in the same situation is $1,100. The $400 difference between the full and partial OAS pensions increases the GIS estimate to $1,500. The combined monthly amount is $1,900. These amounts are hypothetical; the example assumes no deferral increase or additional couple adjustment.

Understanding the result

A future-start calculation shows the projected monthly pension at OAS start as the main answer. Details retain the published-rate starting amount, payment period, ages, growth assumption and horizon. A current calculation uses published rates at the current age entered and does not apply the future-growth assumption.

A combined OAS-and-GIS amount is for the same person, not both members of a couple, and requires compatible calculation bases. An annualized amount is twelve times the monthly estimate, not a schedule of actual payments. Recovery tax is calculated separately.

When both spouses or common-law partners receive OAS, an additional adjustment may apply to their benefits in some circumstances. This estimate shows the standard amount for the selected person and does not determine that adjustment or how it would be allocated.