T1213 calculator + filing guide · Ontario · 2026
Stop loaning the government your refund. Get the support deduction off your paycheque.
Spousal support is tax-deductible. By default, your employer ignores that and takes tax off your full pay — you get the difference back as a refund a year later. Filing Canada Revenue Agency Form T1213 changes that. The calculator below shows the gap. The guide below shows you how to close it.
The gap, in dollars
Per pay period and per year — the money you stop loaning the government once your paycheque is adjusted.
Both paycheque scenarios
What hits your account before and after T1213 is approved, side by side.
Plus a seven-step filing guide
From the calculator output to the moment your payroll office cuts you a new paycheque.
Cairn's T1213 calculator is a free Ontario spousal support calculator that shows the paycheque gap a T1213 closes — no account, no fee. If you pay spousal support under a signed separation agreement or a court order, that payment is deductible from your taxable income. But the payroll system at your employer does not know that. They take tax off your full gross pay all year, and you get the difference back as a refund twelve to sixteen months later when you file your tax return.
For someone in a thirty-to-forty-three percent combined federal and Ontario tax bracket, that is typically three hundred to fifteen hundred dollars per month sitting with the government for the rest of the year — money you cannot use for rent, groceries, or the next thing the kids need.
Canada Revenue Agency Form T1213 — 'Request to Reduce Tax Deductions at Source' — is the form that closes the gap. You send it in with proof of your support obligation. Canada Revenue Agency sends your employer a letter telling them to reduce the tax taken off your paycheque to reflect the deduction. The money stays in your account each payday from that point on.
The calculator runs both scenarios side by side: what your paycheque looks like by default (the refund-at-year-end version) and what it looks like once Canada Revenue Agency has approved your request. The 'per pay period gap' is what stops sitting with the government every two weeks.
Your income, and your spouse's
Both of your gross annual incomes — what you each make in a year before tax.
What you make in a year before tax. Use last year's tax return if it's handy, or your most recent T4.
The same number for your spouse — what they make in a year before tax. Your best honest estimate is fine.
Your kids and how time is shared
How many, their ages, and where they live most of the time.
Children of the relationship who still depend on the two of you. Enter 0 if there are none.
Time together, and ages
How long you've been a couple, plus both your ages.
Count the years you've been a couple, even before marriage. If you lived together for two years before getting married six years ago, enter 8.
We need this to figure out the realistic range for how long support might be paid.
Same reason — age and length of relationship together affect how long support typically lasts.
Methodology reviewed May 6, 2026 · Cross-validated against DivorceMate Tools One · See full sources · Read the guide
Common questions
The questions men ask about Ontario support.
Plain-language answers about how the Federal Child Support Guidelines and the Spousal Support Advisory Guidelines actually work in Ontario.
About Cairn
Cairn is an Ontario-built preparation tool for men going through separation. It gives you orientation, document checklists, and the financial picture in plain language — so you can prepare and then work with a legal professional.
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- Keep these numbers alongside your full separation plan
- Your specific Ontario next steps, in order
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