Child support in Ontario is calculated using the Federal Child Support Guidelines — not negotiated freely between parents. The amount is primarily based on the paying parent's gross annual income and the number of children.
The Basic Support Amount
The Guidelines set out tables showing the monthly support amount based on province and income. For example, in Ontario in 2024:
- $50,000 income, 1 child: approximately $450/month
- $75,000 income, 1 child: approximately $660/month
- $100,000 income, 2 children: approximately $1,450/month
The actual amount depends on the tables — a lawyer or the government's online calculator can provide the precise figure for your income level.
Special and Extraordinary Expenses (Section 7 Expenses)
In addition to the basic table amount, parents share "special expenses" in proportion to their incomes. These include:
- Childcare expenses (daycare, after-school care)
- Medical and dental expenses not covered by insurance
- Extracurricular activities (sports, music lessons, camps)
- Post-secondary education costs
Shared Parenting Arrangements
If both parents have the children at least 40% of the time, the standard table amount may be adjusted using a "set-off" approach — each parent's table amount is calculated, and the difference is paid by the higher earner.
Changing Child Support
Child support can be changed when there's a significant change in circumstances — a major income change for either parent, a change in parenting arrangements, or a child reaching the age of majority. Both parents have an ongoing obligation to disclose income changes.