How Do You Calculate Child Support Where There Is More Than One Other Parent?

child support for multiple parents

In recent years, it has become more common place to see “complex” families where one (or more parents) have children with several other parents, or is a step-parent to children in other families.  So, how child support is calculated when one parent has children with several other parents is an increasingly common question.  The answer is different for parents who are the biological (or adoptive) parent to all the children or the biological parent for child (or children) and a step parent to other children.


Biological and Adoptive Parents


First, biological (and adoptive) parents always pay table support under the Child Support Guidelines. There are some possible adjustments where:

1.                          the payor’s income is over $150,000.00 (pursuant to section 4 of the Child Support Guidelines)

2.                          where paying support causes undue hardship – see section 10 but note that proving undue hardship in court is very hard

3.                          there can also be adjustments for shared or split custody (watch this video  or listen to this podcast if you need to know what those are), but for tax reasons it is better for both parents to pay full support in those situation.

4.                          Also, self-employed people can find that their income for child support is much higher than the income shown on their tax returns.

As the video below shows, other than the above, it is difficult to change Child Support.


Ontario Family Law Podcast

11 - Child Support's Special and Extraordinary Expenses

12 - How Step Parents and Grandparents Can Have to Pay Child Support

17 - Sole Custody, Joint Custody, Shared Custody- How do Judges Decide?

30 - Entitlement to Spousal Support

When the child support payor has all the children with one other parent, calculating child support is easy.  The parents just go to the Child Support Tables (Click here for Ontario’s Tables), find the table for the number of children and then go down that table to the support payer’s income, and the monthly child support amount will be right there.  So, if there are three children, with just two parents, it is a simple matter of looking at the table for three children.  Note, parents share “special and extraordinary expenses” on top of monthly child support. Listen to this podcast for how to calculate the payment of those expenses – they can add a lot to the monthly payments.


Things work differently where the support payor has children with several other parents.  The Child Support Guidelines work on the premise that kids should not be disadvantaged by their parents’ choices, and there are some expenses that can be shared between kids in the same family. So where there are multiple support receiving parents, the support payer pays the full table amount for the number of children with each parent.  If the support payer has one child with one parent and two children with another parent, then the support payer pays the full table amount for one child to the first parent and pays the full table amount for two children to the second parent.  This is a lot more support than just paying for three children together.


Shocked at child support calculation

To illustrate how child support works where the support payer has children with several other parents, consider what would happen in the above situations where the support payer makes $100,000 per year. If the support paying support is paying child support for three children to just one other parent, he or she pays $1920 per month.  Where the support paying parent has to pay child support for one child to one parent and for two children to the second parent, that support owing is $910 to the first and $1471 to the second.  That is $461.00 or 24% more because there are two parents.


Having children with several different parents can mean paying a lot more child support. There can be an adjustment for undue hardship in extreme circumstances, but, as noted above, judges do not like kids to go without because of their parents’ choices.  Judges prefer the parents to make the financial sacrifices, not the kids.


However, if the support payer is, or may be, also required to pay spousal support, Section 38.1 of the Ontario’s Family Law Act, and section 15.3 of the Divorce Act, both say that priority must be given to child support.  So, if a parent is having financial difficulty paying child support to two (or more) parents, spousal support may no longer be payable.  Watch this video for more about factors that affect whether spousal support is payable.


Step Parents

Fistsfulls_of_Money from child support

Step parents have to pay child support when they stand in the place of a parent to the children. For more on when that can happen, listen to this podcast or check out this page.  It is often the case that step parents end up paying full child support in the same way as biological parents.  However, section 5 of the Child Support Guidelines, gives Judges the discretion to require step-parents to pay an amount that is different from the table amounts.  While the law expects that kids will share in the wealth of their parents, it does not expect that kids, or one of their parents, will get a windfall as a result of receiving child support from both a biological parent and step-parents.  Where the biological parent is paying support, judges will often reduce the amount of child support that a step-parent pays if the combined support payments would be more than the child needs.  However, there is no set formula for doing that calculation.


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Child support where there are multiple parents, or more complicated parenting arrangements can be difficult to determine. There are a lot of factors that come into play, and there may be additional ways that the law can help you. The best way to protect yourself, your children and , your financial security, is to find out how the law applies specifically to your situation and what steps you should take to get things to work out for you. Contact Certified Specialist in Family Law (and author of the book to the left), John Schuman, by emailing him, calling 416-446-5869, or using the contact form below.  We answer all inquiries promptly and we can arrange for you to come in quickly for a consultation (charged at a reduced hourly rate). 


You can get a lot more information about Ontario Family Law issues, including a comprehensive explanation of child support, spousal support, property division, and most other common family law issues by downloading this $9.99 Kindle eBook, Kobo eBook, or iBook for your iPad or iPhone or ordering it from Amazon as a paperback.


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