Ontario Child Support Guidelines Explained in Plain Language

If you are separating, you have probably heard that child support is "just a formula." That is mostly true, and the formula comes from the Child Support Guidelines. Knowing what the Guidelines are, and what they leave open, makes it easier to understand any number you are given.

This article explains the Guidelines in plain words for families in Ontario. It covers which rules apply to you, what they set, who counts as a child and where the amount can differ. It is general information, not advice on your situation.

What the Guidelines are for

The Federal Child Support Guidelines aim to set a fair standard of support for children and to reduce conflict between spouses. Instead of arguing over what each child costs, parents start from a published table.

Under the Divorce Act, a court may order a spouse to pay support for any or all children of the marriage, and the order must follow the applicable guidelines. The basic amount is the table amount for the number of children, plus any section 7 expenses, and it is the presumptive amount, not a rough suggestion.

Which Guidelines apply to you

There are federal Guidelines and Ontario's own set. In general, the federal Guidelines and the Divorce Act apply to married spouses who are divorcing. Unmarried parents, and married parents who are not seeking a divorce, are generally dealt with under Ontario's Family Law Act and the Ontario child support guidelines. How those rules apply to you depends on your situation, so a lawyer can confirm which applies.

In practice, the table amounts are the same starting point for most families. Ontario's government says the 2025 table amounts apply to all Ontario child support matters starting October 1, 2025, but the 2025 tables do not automatically change an order made before that date.

What the Guidelines set

The basic amount is the amount in the applicable table for the number of children under the age of majority, plus any special or extraordinary expenses under section 7. The table amount depends on three things: the paying parent's annual income, the number of children and the province where the paying parent lives.

Special or extraordinary expenses are paid on top of the table amount when a court decides on them at a spouse's request, after considering whether each expense is necessary in the child's best interests and reasonable given the family's means. They include:

• Child care costs linked to a parent's employment, illness, disability or education.
• The child's share of medical and dental insurance premiums.
• Health-related costs above insurance reimbursement by at least $100 a year.
• Extraordinary school or extracurricular costs, and post-secondary education expenses.

No child support is payable under the federal tables from a payor whose annual income is below $12,000.

Who counts as a child

Under the Divorce Act, a child of the marriage is a child of two spouses or former spouses who is under the age of majority and has not withdrawn from their charge. It also includes an adult child who cannot become independent because of illness, disability or another cause.

For an adult child, the court may apply the Guidelines as if the child were a minor. If that seems inappropriate, it may set the amount it considers appropriate, having regard to the child's condition, means, needs and other circumstances.

A stepparent can also be covered. A child of the marriage includes a child for whom one spouse is the parent and the other stands in the place of a parent. For that spouse, the amount is what the court considers appropriate, having regard to the Guidelines and any other parent's legal duty to support the child, so it is not automatically the table amount.

When the amount can differ, and what to do next

The table is the starting point, but the Guidelines allow departures in specific cases, including when the payor's income is over $150,000:

• Income over $150,000: the court may order the full table amount, or, if it considers that inappropriate, the table amount on the first $150,000 plus an amount it considers appropriate for the income above that.
• Shared parenting: if each parent has the child at least 40% of the time over a year, the court looks at both parents' table amounts, the increased costs of shared care and each household's circumstances, with no automatic formula.
• Split parenting: if there is more than one child and each parent has a majority of parenting time with at least one of them, support is the difference between the two table amounts.
• Undue hardship: a different amount may be ordered, but the claim must be denied if the claiming household would have a higher standard of living.
• Consent: the court can approve a different amount if it is satisfied that reasonable arrangements have been made for the child's support. Parents cannot simply contract out of support.

To prepare, gather your last three years of tax returns and notices of assessment, and note your parenting schedule. If your family has shared care, a self-employed parent or a high income, speaking with a lawyer before you agree to a number is worthwhile.

Frequently asked questions