Unlike the child support tables, the Spousal Support Advisory Guidelines are not legislation — they produce a range, not a figure, and only once entitlement is already established.
“My common-law separation didn't fit the assumptions I'd made from friends' experiences, and having that explained clearly cleared up a lot of confusion.”K.M. · Common-law separation · Niagara Region
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Enter both gross incomes, the years you lived together, and the lower earner's age at separation. This applies the without child support formula from the Spousal Support Advisory Guidelines and returns an amount range and a duration range.
The first tab above calculates the guideline child support table amount, if you need that too, or use the dedicated child support calculator →.
The calculator above applies both formulas for you.
Amount. 1.5% to 2% of the difference between the spouses' gross incomes for each year you lived together, to a maximum of 50% of that difference. The maximum is reached at 25 years. The top of the range is also capped at the point where the spouses' net incomes would be equalised.
Duration. Half a year to one year of support for each year of cohabitation — unless the relationship ran 20 years or longer, or the rule of 65 → applies, in which case duration is indefinite.
The range is deliberate. Where a case sits inside it depends on the strength of any compensatory claim, the recipient's needs, the payor's ability to pay, property division, and self-sufficiency incentives — see who qualifies for entitlement → first.
A calculator that faked this would hand you a confident, wrong number.
When child support is being paid, the Guidelines switch to a different formula built on individual net disposable income: each spouse's Guidelines income, less child support, tax and deductions, plus government benefits and credits — then solved by iteration to land within a target share of the combined total.
That requires modelling federal and Ontario tax, credits and benefits for two households. Family lawyers use dedicated software for it. A calculator that faked it would hand you a confident, wrong number to negotiate against, so this one does not — the child support tab above is still exact, though.
Say the higher earner made $110,000 and the lower earner made $45,000, together for 12 years, with the lower earner 45 at separation and no dependent children:
Because the relationship ran under 20 years and the years-plus-age total (12 + 45 = 57) is under 65, duration here is time-limited rather than indefinite. Run your own incomes, years and age in the calculator above.
No. Unlike the child support tables, the Spousal Support Advisory Guidelines are not legislation and are not binding. They are an advisory tool, used heavily by courts and lawyers across Canada to produce a range rather than a figure.
Because doing it honestly is not possible from a handful of inputs. The with child support formula works from each spouse's individual net disposable income — Guidelines income less child support, tax and deductions, plus government benefits and credits — and is solved by iteration. It needs tax software. Producing an approximation would give you a number that looks authoritative and is wrong, so this tool declines to.
Not permanent. It means the duration is not specified in advance. Support remains open to review and variation as circumstances change — retirement, re-partnering, a material change in either income. It arises where the relationship lasted 20 years or more, or under the rule of 65.
Where the relationship lasted at least five years, and the years of cohabitation plus the recipient's age at separation total 65 or more, duration is indefinite rather than time-limited. It exists because a shorter marriage ending later in life leaves much less time to become self-sufficient.
Less reliably. Above a payor income of $350,000 the Guidelines are treated as a ceiling and courts apply discretion. Below $20,000 support is usually not ordered at all, and between $20,000 and $30,000 the formula needs adjustment.
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