Child Support in Canada: How It Works

If you are trying to work out child support, you are probably worried about one of two things: whether you can afford to pay it, or whether you can afford to live without it. Both worries are real. The good news is that in Canada, the starting number is not a guess or a fight. It comes from a table, and once you know how that table works, most of the uncertainty goes away.

This guide explains how the base amount is set, what gets added on top, where people commonly get it wrong, and what to do this week to get a number you can rely on.

How is the child support table amount calculated?

Every calculation starts with the Federal Child Support Tables, which are part of the Federal Child Support Guidelines. The tables are different for each province and territory because provincial tax rates differ.

The three inputs are:

• The paying parent's gross annual income
• The province or territory where the paying parent lives
• The number of children being supported

The output is a monthly amount. There is no formula for you to run: you find the income in the table and read across.

The tables were updated on October 1, 2025, the first update since 2017. To give you a sense of scale, here are some amounts from the 2025 simplified tables for Ontario:

Other provinces produce different numbers for the same income, so always use the table for the province where the paying parent lives. These are base amounts. Section 7 expenses, explained below, are added on top.

Gross income, not take-home pay

The single most common mistake is using net income instead of gross.

The Guidelines use income before tax. Section 16 starts with "total income" on your tax return (line 15000 on your Notice of Assessment) and then applies the adjustments in Schedule III. Some deductions are allowed, such as union dues. RRSP contributions are not, so putting money into your RRSP does not reduce your income for child support.

If you have been working from your pay cheque deposit, your number is almost certainly too low. If your income is from a business, commission or contracts, the calculation has more steps. Our guide to self-employed and variable income walks through them.

What are section 7 expenses?

Section 7 covers "special or extraordinary expenses". These are added to the table amount and usually shared in proportion to each parent's income. A court looks at whether each expense is necessary in the child's best interests and reasonable given the parents' means and how the family spent money before separation. So an expense being on the list does not guarantee it will be shared; it has to be reasonable too.

The categories are:

• Childcare needed because of a parent's work, illness, disability, or education or training for work
• The part of medical and dental insurance premiums that covers the child
• Health-related costs that exceed insurance reimbursement by at least $100 a year, such as orthodontics, counselling, physiotherapy, speech therapy, prescription drugs, hearing aids and glasses
• Extraordinary costs for primary or secondary school, or other programs that meet the child's particular needs
• Post-secondary education
• Extraordinary extracurricular activities. "Extraordinary" matters here. A recreational soccer league may not qualify; competitive hockey or intensive music training often does

The proportional split works like this. If Parent A earns $80,000 and Parent B earns $40,000, combined income is $120,000. Parent A has two thirds of the combined income and pays about 67 percent of agreed Section 7 costs; Parent B pays about 33 percent. That is separate from, and on top of, the table amount.

How does shared parenting change child support?

When each parent has the child at least 40 percent of the time over a year, Section 9 of the Guidelines applies. The court must take into account:

• The table amount for each parent
• The increased costs of running two homes for the child
• The conditions, means, needs and other circumstances of each parent and the child

Forty percent is roughly 146 days a year. Overnights are the most common way to count, but courts look at the whole picture of time and responsibility.

Shared parenting does not make support disappear. Usually the two table amounts are set off against each other, so the higher earner pays the difference, and then that figure is adjusted for actual costs. Our guide to child support in shared parenting explains the calculation with an example.

When income isn't what it seems: imputing income

Courts can impute income, which means treating a parent as earning more than they report. Section 19 of the Guidelines lists situations where this can happen, including:

• A parent is intentionally unemployed or underemployed, unless that is needed for a child's care or for the parent's reasonable health or education needs
• Income has been diverted, for example through a corporation or to a family member
• A parent has not provided income information they were required to provide
• A parent deducts expenses unreasonably, such as running personal costs through a business

When income is imputed, support is calculated on the figure the court decides is fair, not the figure on the tax return.

What happens to child support when income changes?

Support should follow income. Under Section 25 of the Guidelines, once there is a child support order, the recipient can ask in writing, once a year, for the paying parent's tax returns and notices of assessment. Many agreements go further and require both parents to exchange income documents every year by a set date, with support recalculated automatically. That clause prevents a lot of conflict.

If the paying parent's income rises and support is not adjusted, the recipient can claim the difference retroactively. In D.B.S. v. S.R.G. (2006), the Supreme Court of Canada said retroactive awards usually reach back to when the recipient gave effective notice, and generally no more than three years before formal notice, though that limit can be extended where the payor behaved in a blameworthy way, such as hiding an income increase. The safest approach for a payor is to disclose increases and adjust promptly.

Quebec: a separate system

Quebec uses its own child support model, set by provincial regulation, rather than the federal tables. It looks at both parents' incomes and the parenting arrangement and produces different amounts. If both parents live in Quebec, use the Quebec model. The Quebec government publishes its own form and calculation tool.

If you are in the United States

The US has no single national table. Each state sets its own child support guidelines. According to the National Conference of State Legislatures, 41 states use an "income shares" model, which combines both parents' incomes; six use a percentage of the paying parent's income; and three use the Melson formula. Your state's child support agency publishes its worksheet or calculator. Your state hub is the best place to start.

What can parents not agree to on child support?

Child support is the child's right, not the parents'. You can agree to pay more than the table amount. Agreeing to pay less is risky. Under the Divorce Act, a court can approve a different amount only where reasonable arrangements have been made for the child's support, for example where a property settlement directly benefits the child. Otherwise, a below-table agreement can be revisited, and the recipient can usually ask a court for the table amount regardless of what was signed.

That matters if you are tempted to trade child support for the house or for peace. It can come back years later, with arrears.

What to do this week

1. Find your most recent Notice of Assessment, and ask the other parent for theirs. If you can't get it, use the last tax return and recent pay stubs as a placeholder.
2. Look up the table amount for the paying parent's province and the number of children using the FairWell child support calculator or Justice Canada's online look-up.
3. List current and expected Section 7 costs: childcare, braces, therapy, sports, tutoring, school trips. Gather receipts or quotes.
4. Count parenting time on a calendar for a full year if you think you might be near 40 percent.
5. Start paying or receiving something now, even before an agreement is signed, and keep a record. Informal payments made by e-transfer leave a trail.
6. Check the financial disclosure checklist so you know what documents you will both need.

If your ex is refusing to disclose income, is self-employed with complicated finances, or you are being pressured to accept less than the table, speak to a family lawyer before you sign anything. Many offer a fixed-fee first consultation, and legal aid may be available depending on your income.

Common questions

How much child support will I pay or receive?

Look up the paying parent's gross income in the federal table for their province and the number of children, then add a share of any Section 7 expenses. The FairWell calculator and Justice Canada's online look-up both use the official tables.

Does child support change if I have the kids half the time?

Usually yes, but it rarely goes to zero. With at least 40 percent parenting time each, Section 9 applies and the two table amounts are typically set off, then adjusted for actual costs.

Is child support taxable in Canada?

No. For orders and agreements made after April 1997, child support is not deductible for the payor and not taxable for the recipient.

What if my ex stops paying?

Every province and territory has a maintenance enforcement program that can collect support for you, including by garnishing wages. Register your order or filed agreement with it and keep records of every payment.

When does child support end?

It continues while the child is a "child of the marriage", which includes children under the age of majority and older children who cannot support themselves, often because they are in full-time post-secondary education. Your agreement should say how this is handled.

This guide is legal information, not legal advice, and it is written for a general audience across Canada and the United States. Family law is provincial and state-based and changes over time. Before you rely on anything here for your own situation, confirm it with a qualified family lawyer in your province or state. FairWell can connect you with one through the professional directory.