Using the Ontario Support Calculator

What it can estimate

• Child support
• Spousal support without child support
• Spousal support with child support
• Combined child and spousal support outcomes

How the calculator works

You enter each person’s income, the number of children, the parenting arrangement, and the support issues. For child support it uses the applicable Federal Child Support Tables — the tables were updated effective 2025, and the right one depends on the support period. For spousal support it applies the Spousal Support Advisory Guidelines (SSAG). The SSAGs are not legislation, but courts and family law professionals widely use them to estimate the amount and duration of spousal support.

Calculating child support

Child support is usually calculated first. The table amount is based mainly on the payor’s income, the number of children, and the province. That amount is the starting point, not always the final number — additional expenses, parenting arrangements, income issues, or hardship can affect the result.

Primary care

Where the children live primarily with one parent, the other parent usually pays the table amount based on their income and the number of children. This is the most straightforward calculation.

Shared parenting

Shared parenting applies where each parent has at least 40% of parenting time over the year. Many people assume shared parenting means no child support — that is not correct. The calculator usually estimates a set-off: each parent’s table amount is calculated and the higher-income parent pays the difference. A court may also consider the actual increased costs of shared parenting and the child’s circumstances.

Special or extraordinary (Section 7) expenses

On top of the table amount, child support can include special or extraordinary expenses — childcare, certain medical or dental costs, health-related expenses, post-secondary costs, or appropriate extracurricular expenses. These are usually shared in proportion to each parent’s income, after accounting for tax credits, subsidies, or benefits.

Calculating spousal support

Spousal support is different from child support, and child support generally has priority. The calculator can estimate spousal support using either the without child support formula or the with child support formula. Choosing the right formula matters — the wrong one produces inaccurate results.

Without child support formula

Used where there are no dependent children for whom child support is being calculated. It focuses on the spouses’ incomes, the length of the relationship, and the income difference, producing a range for both the monthly amount and the duration. It often applies where there were no children, the children are grown, or the only issue is between the spouses.

With child support formula

Used where child support is also being calculated. It is more complex because it accounts for the children’s needs, the child support obligation, taxes, benefits, and each household’s available income. Unlike the without-child formula, it works from net disposable income rather than simply comparing gross incomes — so accurate parenting, child support, and income information significantly changes the range.

Entitlement comes first

A calculator can estimate numbers, but the first spousal-support question is not "how much?" — it is entitlement. The person seeking support must have a legal basis for it. The SSAGs do not create entitlement, and income disparity alone does not automatically mean support will be ordered. Ontario recognizes three broad foundations.

Compensatory

Addresses economic advantages or disadvantages arising from the relationship — for example, a spouse who stayed home or reduced work to care for children, supported the other’s career or education, moved for the other’s job, or left with reduced earning capacity because of roles adopted during the marriage.

Non-compensatory

Based on need, dependency, or hardship after separation, even without a specific career sacrifice. A long relationship can create financial interdependence, or one spouse may be unable to meet reasonable needs after separation.

Contractual

Comes from an agreement between the spouses — a marriage contract, cohabitation agreement, separation agreement, or other written agreement dealing with support. Courts take such agreements seriously, especially where negotiated fairly with proper disclosure and legal advice, though they can still be challenged in some circumstances.

Entitlement does not always mean support is paid

Even where entitlement exists, support may not be payable in a meaningful amount. A zero range for amount is not the same as a lack of entitlement — it may simply reflect a current inability to pay. This can happen where:

• the payor cannot afford to pay
• child support absorbs most of the available income
• the SSAG range is very low, or the correct calculation is near zero
• the recipient’s need is limited
• the relationship was short or incomes are similar
• other financial obligations affect the result

How courts treat spousal support

In Ontario, spousal support is discretionary. The SSAGs help estimate amount and duration but do not replace judicial discretion. A court may consider the length of the relationship, the roles each spouse played, incomes and earning capacities, childcare responsibilities, the standard of living during the relationship, financial need, economic disadvantage, any agreement between the spouses, the payor’s ability to pay, and whether support should be time-limited, indefinite, reviewable, or variable.

How spousal support can end, change, or be reviewed

Support may end on a fixed end date, by agreement, by court order after a variation, when the recipient becomes self-sufficient, on the payor’s retirement, on a material change in circumstances, through a lump-sum payment, or after a specified event. "Indefinite" does not mean permanent — usually it means there is no fixed end date when the order or agreement is made. A review happens when the agreement says support will be reconsidered later; a variation usually requires a material change such as a significant income change, job loss, illness, retirement, or a change in parenting responsibilities.

Enforcement in Ontario

When an Ontario court makes a child or spousal support order, it is generally filed with the Family Responsibility Office (FRO), which collects, distributes, and enforces support payments. Once there is a court order, support is not just a private promise — enforcement mechanisms may be available if support is not paid.

Why use the calculator

• Estimate child support
• Compare primary-care and shared-parenting outcomes
• Estimate spousal support with or without child support
• Understand how child support affects spousal support
• Identify whether special expenses may matter
• See how different income assumptions change support
• Prepare for negotiation, mediation, or a legal consultation

Important notice

The calculator provides estimates only. It does not determine legal entitlement to spousal support, does not replace independent legal advice, and does not guarantee what a court will order. Results can change depending on income, disclosure, parenting time, tax assumptions, special expenses, entitlement, ability to pay, and future changes in circumstances. In Ontario, obtain legal advice before relying on a support calculation or signing an agreement about child or spousal support.