OAS Clawback Calculator

The chart for line 23500 in the CRA's Federal Worksheet does it in three steps: take your adjusted net income, subtract the threshold for the year, and multiply what is left by 15%. Your repayment is whichever is less, that amount or the OAS pension you received in the year (plus any net federal supplements, less any overpayment recovered). The result goes on both line 23500 and line 42200 of the return.

canada.ca's example: $100,000 of income in 2025 is $6,546 above the $93,454 threshold, and 15% of that is $981.90, repaid over July 2026 to June 2027. At $130,000 the repayment is $5,481.90 and you keep $3,309 of the $8,791 maximum paid in 2025 to someone aged 65 to 74.

Net world income includes the OAS pension itself. For Canadian residents it is the net income on line 23400 of the return, less universal child care benefit and RDSP income and any EI benefits repaid, plus any repayments of those. Non-residents report it on the Old Age Security Return of Income, which lists employment, business, pensions, social security, capital gains, rental property, interest and dividends among the income it includes.

Section 180.2 of the Income Tax Act has the tax withheld from each monthly OAS payment, based on the income of a base year: for payments from July to December it is the previous calendar year, and for January to June the year before that. So your 2025 return sets the deductions from July 2026 to June 2027, and your 2026 return those from July 2027 to June 2028. ESDC describes it as your estimated repayment divided by 12 and deducted from each payment; Service Canada sends a letter with the amount, and a deduction can never be more than the payment.

The deductions are a prepayment. Each year's actual recovery tax is worked out on that year's return, the tax withheld (box 22 of the T4A(OAS) slip) is claimed on line 43700, and the CRA refunds any excess or you pay the difference. If your income was above the threshold last year but will be substantially lower this year, you can send the CRA Form T1213(OAS) to ask for smaller deductions from July.

It counts the maximum OAS pension, which is what you receive with 40 years in Canada after 18 and a start at 65. A partial or deferred pension changes the OAS you receive, and so the most that can be clawed back, but not the 15% rate or the threshold. When you received OAS for only part of the year, the months are counted at the end of the year. The age group applies to the whole year.

The monthly deduction is capped at the latest published monthly pension, and the calculator does not include non-resident tax: for people living outside Canada, the recovery tax and non-resident tax together cannot be more than the OAS paid in the month. To estimate the pension itself at each start age, use the OAS calculator; for low incomes, the GIS calculator shows the Guaranteed Income Supplement paid on top of OAS.