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  • Writer's pictureSamantha Prescott

How To Calculate Child Support in Ontario

Updated: Nov 8, 2023

If you and your spouse are separating and you have a child, or children, you most likely have a lot of questions about child support. This is normal given that child support is a critical aspect of ensuring the well-being of your child(ren) as you navigate a separation.

I hear a lot of people make comments like, “I don’t need support”, or, “I am not going after support” as though its something to be proud of. Child support is considered the right of the child; not pursuing support can be detrimental to your child(ren) and family. You will never be considered “greedy” or “unreasonable” for pursuing support. It is important to understand what support is and how it is calculated before making a decision that will significantly impact your child(ren).

This blog post will guide you through the process of calculating child support in Ontario and provide links and resources where you can find more information.

1. Income Determination

The first step in calculating child support in Ontario is determining the income of both parents. You will not be able to calculate support in most cases without knowing the income of the paying parent. The GROSS amount of income is used for this calculation. For individuals who are employees, your line 1500 income is the number you will use (plus any other income you may earn such as rental income or dividends). If you are self-employed, the number you use will depend on many factors and a lawyer should be consulted in that circumstance. You must use the most current information available to you when calculating child support.

2. The Federal Child Support Guidelines

Child support calculations in Ontario are based on the Federal Child Support Guidelines. The guidelines consider the paying parent's income, the number of child(ren), and their province of residence. It's important to note that child support is generally paid by the parent with whom the child does not primarily reside. If you share parenting time, child support with be “set-off” (see #5 below). In either scenario, the Federal Child Support Guidelines are used to complete the calculation.

3. Determining the Base Amount

The Federal Child Support Guidelines provide a table that outlines the base amount of child support payable based on the paying parent's income and the number of child(ren). The table takes into account the cost of raising child(ren) at various income levels. To access the free Federal Child Support Guidelines calculator, click here Scroll down to the bottom of the page, enter the paying parent’s line 1500 income plus any other income they earn, your province (or the province where the child(ren) reside), and the number of children and click “Look-up”. This is the amount the paying parent must pay on a monthly basis.

4. Special and Extraordinary Expenses

In addition to the base amount, parents may be responsible for special or extraordinary expenses related to their child(ren). These expenses can include child care costs, medical and dental insurance, and extracurricular activities. Special expenses are typically shared in proportion to the parents' incomes.

5. Shared Parenting Time

In cases of “shared parenting time” (meaning when the child(ren) spend at least 40% of time with one of the two parents), child support is “set off”. The higher income earner of the two parents will still owe child support, but the amount owing will take into account what the other parent makes. Here’s how to make that calculation:

1) Calculate support owing for either parent by following #3 above “Determining the Base Amount”;

2) Minus the smaller amount owing, from the larger amount owing. The amount remaining is what the higher income earner must pay each month to the lower income earner;

3) Example: Riley and Dayna have shared parenting of their one child, Steven. Riley’s gross income is $70,000. Dayna’s gross income is $40,000.

Using the Federal Child Support Tables, Riley would have to pay monthly child support of $654 based on their gross income of $70,000 for one child. Dayna would have to pay monthly child support of $359 based on their gross income of $40,000 for one child.

The difference between $654 and $359 is $295. Riley pays Dayna $295 in monthly child support for Steven.

6. Imputed Income

In some cases, the court may impute income to a parent if it's believed that they are intentionally underemployed or not earning their full potential. This is done to ensure that child support is fair and equitable. Don’t quit your job or take a lesser paying job to lower your support. This will only have negative consequences for you and your family.

If you and your spouse have a complicated parenting schedule, or complicated income structures, you may be left with many questions regarding child support. In these situations, its best to reach out to a lawyer so they can address your specific situation.

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Written by Samantha Prescott

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