The portion of a lawyer's bill attributable to obtaining, increasing, or enforcing a child support order is tax-deductible. The cost of defending a claim for child support is not deductible. Read the Canada Revenue Agency's (CRA) [http://www.cra-arc.gc.ca/tx/tchncl/ncmtx/fls/s1/f3/s1-f3-c3-eng.html#N10C4B Canada Revenue Agency's Income Tax Folio S1-F3-C3, Support Payments] for the fine print, and speak to an accountant to get advice to see if you qualify to write off the portion of your lawyer’s bill that relates to child support.

In a shared parenting situation, where each parent has a duty to pay child support to the other parent, the higher-income parent often just pays the difference between the higher amount they owe and the lower amount they would receive from the lower-income parent. This difference is called a ''set-off amount''. In a court order or agreement, however, it matters how this arrangement is worded. Recently, the CRA Canada Revenue Agency has decided that if the agreement or order says that only the higher income-earning parent pays child support, the CRA will treat the situation as if there is only ''one'' payor and ''one'' recipient of child support.

In cases like this, the CRA Canada Revenue Agency will not allow the parents to share child tax deductions or grants, and will not allow the parents to claim the children as dependents when they file their taxes. As a result, it's a good idea to make sure that your agreement or order says that ''each'' parent pays child support to the other. And it's probably best to not even mention the set-off amount actually paid. You can do the math to figure that out yourself. An agreement might, for example, say something like this: