Child Support Calculator Ontario: How to Calculate 2025 Amounts

If you're trying to figure out child support in Ontario, the numbers can feel like a maze — especially when both parents share parenting time. The 2025 Federal Child Support Tables, effective October 1, 2025, set fixed monthly amounts for incomes up to $150,000, but shared custody can shift the final payment significantly.

Official table effective date: October 1, 2025 ·
Income cap for standard table: $150,000 annual income ·
Parenting time threshold for adjustment: 40% or more ·
Free official lookup tool: justice.gc.ca child support table look-up

Five quick facts, one pattern: all amounts are set at the federal level, but parenting time can rewrite the total.

How do I use the child support calculator for Ontario?

Follow these steps to get the right amount:

1. Determine the paying parent's annual before-tax income from all sources.
2. Use the official DOI Canada table look-up to find the base monthly amount.
3. Calculate the parenting time split (percentage of overnights or hours).
4. If shared custody (40%–60% time), apply the set-off formula using both parents' table amounts.
5. The higher-income parent pays the difference; extraordinary expenses are split proportionally.

What income information do I need?

You need the paying parent's before-tax annual income from all sources. The Department of Justice Canada (federal regulator) requires this to determine the table amount. For self-employed individuals, net income before taxes is used, based on the latest tax return.

How to input parenting time

Parenting time is measured as a percentage of overnights or hours. Custody X Change (family law tool provider) explains that when neither parent exceeds 60% of time, both incomes may be considered. You input the percentages into the calculator or directly into the set-off formula.

Are there free calculators available?

Yes. The official free look-up is on justice.gc.ca. Many private sites also offer tools — but DOI Canada warns that only the official version is legally binding. Private calculators add extra features like spousal support estimates but should be verified against the real tables.

How much is child support in Ontario for one child?

What is the base amount for one child at $50,000 income?

For one child, with the paying parent earning $50,000 per year, the 2025 Federal Child Support Table sets the monthly amount at $485. This is a fixed figure from the DOI Canada table look-up and applies when the paying parent lives in Ontario.

How does the amount change with higher income?

As income rises, the table amount increases in brackets. At $100,000 annual income, one child yields approximately $895 per month. At $150,000, it reaches about $1,329. DOI Canada publishes the full schedule.

Are there special rules for low-income payors?

Yes. If the paying parent's income is below approximately $20,000, the table amount is reduced. The guidelines allow for a "self-support reserve" so the payor can meet basic needs. DOI Canada (policy update) explains that these rules are part of the 2025 reforms.

How does 50/50 custody affect child support in Ontario?

What is the definition of shared parenting time?

Shared custody is defined as parenting time of 40% to 60% of the time. Custody X Change notes that when any parent has more than 60% time, the parent with less time pays support.

How is the set-off formula applied?

Under shared custody, the set-off formula applies: each parent's table amount is calculated, then the higher-income parent pays the difference. For example, if Parent A's amount is $800 and Parent B's is $400, Parent A pays $400. Custody X Change provides this calculation logic.

When does the full table amount still apply?

If parenting time is not shared (one parent has less than 40% time), the full table amount from the payor is used. Custody X Change clarifies that only when both parents' incomes factor into the formula does the set-off apply.

Where can I find the official child support table for Ontario?

What is the URL of the official look-up tool?

The official tool is at justice.gc.ca child support table look-up. It requires selecting the number of children, payor's province, and income.

How do I download the PDF version?

The same page offers a PDF download of the full 2025 Federal Child Support Tables. DOI Canada provides both the interactive tool and the PDF directly.

Which table year should I use for 2025–2026?

From October 1, 2025 onward, use the 2025 tables. For periods before that, the 2017 tables apply (DOI Canada). The 2026 tables are not yet published.

What is the difference between the Ontario and Canada child support calculator?

Does the federal calculator apply to Ontario?

DOI Canada states that Ontario uses the Federal Child Support Tables as its base, with no provincial variation for the standard table amounts. The same calculator works for all provinces except Quebec.

Are there province-specific adjustments?

Some provinces have their own guidelines, but Ontario relies on the federal framework. However, DOI Canada notes that provincial law may affect enforcement and variation rules.

Which calculator should I trust?

Trust the official DOI Canada look-up. Private calculators from sites like Custody X Change or PLSLawyers (Ontario family law firm) add useful context but are not legally binding.

"The 2025 look-up should be used to calculate child support amounts from October 1, 2025 onward."

— Department of Justice Canada (federal regulator)

"For 50/50 parenting time, the payor’s support may be reduced significantly, but each case is unique."

— PLSLawyers (Ontario family law firm)

The 2025 Federal Child Support Tables give Ontario parents a clear number for incomes up to $150,000, but shared custody rewrites the equation. For a payor with 50/50 parenting time and a similar-income co-parent, monthly support may drop sharply — sometimes to zero. The implication is clear: get both incomes and the exact parenting percentage into the official DOI Canada calculator, then assume extraordinary expenses will be split. For Ontario parents facing a separation or modification, the choice is simple: use the official table, or risk an incorrect order that a court will correct later.