Child support is the child's right, not a favour between parents. Ontario uses the Federal Child Support Guidelines: a table amount from the payor's income, plus a share of special or extraordinary expenses.
The number is usually straightforward when income is straightforward. It becomes a file when income is hidden, self-employed or fluctuating — that is where a lawyer earns the fee.
The table amount
Look up the payor's annual income and the number of children on the federal table for Ontario. Shared parenting time can change the math — both parents' incomes and the time each has the child enter the analysis.
Special and extraordinary expenses
Section 7 expenses — childcare, health premiums, extraordinary extracurriculars, post-secondary — are shared in proportion to income, on top of the table amount. 'Extraordinary' is a legal word; not every activity qualifies.
Income that is not a T4
Self-employment, cash, corporate income and imputed income are where Guidelines files are won or lost. Disclosure and, where needed, a motion to impute income are the tools.
Enforcement and change
The Family Responsibility Office collects and enforces support once an order or filed agreement is with them. Changing the number requires a Motion to Change or an amending agreement — FRO cannot rewrite the order.