Calculating Child Support Payments Ontario

How to Calculate Child Support in Ontario

Ontario's child support system is based on a formula that considers both parents' incomes and the number of children involved. The calculation follows these key steps:

Step 1: Determine Combined Income

Add the net incomes of both parents to get the combined income. This includes all sources of income before taxes.

Step 2: Apply the Child Support Formula

The Ontario Child Support Guidelines use a specific formula to determine the weekly child support amount:

The percentage used depends on the number of children:

• 1 child: 17.44%
• 2 children: 25.67%
• 3 children: 29.96%
• 4 children: 32.76%
• 5+ children: 34.82%

Step 3: Calculate Weekly Amount

Divide the result by 52 to get the weekly child support amount.

Step 4: Adjust for Special Circumstances

Additional factors may increase or decrease the base amount, such as:

• Medical expenses
• Extraordinary expenses
• Special needs
• Parental alienation

Factors That Affect Child Support Payments

Several factors influence the final child support amount in Ontario:

Number of Children

The more children involved, the higher the percentage applied to the combined income.

Parents' Incomes

Higher combined income results in larger child support payments.

Special Needs

Children with special needs may qualify for additional support.

Medical Expenses

Approved medical expenses can increase the child support amount.

Parental Alienation

If one parent is alienating the children, the court may adjust support.

Worked Examples

Example 1: Single Child

Parent 1 income: $40,000/year

Parent 2 income: $30,000/year

Combined income: $70,000

Percentage for 1 child: 17.44%

Calculation: ($70,000 × 0.1744) ÷ 52 = $230.58 per week

Example 2: Two Children

Parent 1 income: $60,000/year

Parent 2 income: $50,000/year

Combined income: $110,000

Percentage for 2 children: 25.67%

Calculation: ($110,000 × 0.2567) ÷ 52 = $443.27 per week