The Federal Child Support Guidelines (SOR/97-175) are the cornerstone of child support law in Canada. Enacted under the Divorce Act in 1997, they replaced the old discretionary regime with a standardized, table-based system. The goal is predictability and fairness: given a payor's income, province, and number of children, the table produces a specific monthly amount. This removes most of the guesswork and negotiation that characterized the pre-1997 system.

This article explains how the tables work, what "guideline income" means, how the system handles high and low incomes, and what Schedule III adjustments are.

How the Tables Work

The child support tables are organized by province, income level, and number of children (1 through 6+). Each province has its own table because provincial tax rates differ — the tables are calibrated so that the after-tax support available to the child is roughly consistent regardless of where the payor lives. The payor's province of residence determines which table applies.

Within each table, income is divided into $1,000 bands. Each band specifies a base monthly amount plus a percentage rate applied to the income above the band's floor. For example, in Ontario with 2 children, the band for $85,000–$85,999 specifies a base of $1,296 per month plus 1.56% of income above $85,000. At exactly $85,000, the table amount is $1,296 per month ($15,552 per year).

What Is "Guideline Income"?

The income used for the table lookup is not simply salary or wages. "Guideline income" under the Federal Child Support Guidelines includes income from all sources as reported on the T1 tax return, with specific adjustments prescribed by Schedule III of the Guidelines. The starting point is total income (Line 15000), but the final number can be significantly different.

Common adjustments include:

High Income: Above $150,000

For payors earning over $150,000, section 4 of the Guidelines gives courts discretion. The table amount for the first $150,000 is calculated normally. For the income above $150,000, the court may order the table amount (continuing the formula), a different amount based on the child's actual needs, or a combination. The court considers the condition, means, needs, and other circumstances of the child, and the financial ability of each parent.

In practice, many courts simply apply the table formula to the full income — but they are not required to. The calculator applies the table formula to all income and flags cases above $150,000 with a note that judicial discretion may apply.

Low Income: Below $16,000

The federal child support tables begin at $16,000. Below this threshold, the table returns $0 — not because no obligation exists, but because the tables were not designed for income levels where the payor may not be able to meet their own basic needs. Courts retain discretion to set an amount in these cases, but the table itself prescribes nothing.

Designated Provinces

Three provinces — Manitoba, New Brunswick, and Quebec — are "designated provinces" under the Guidelines. In designated provinces, the provincial child support tables replace the federal tables. The provincial tables may use different income bands, rates, or calculation methods. Quebec's system (Form 1) is the most distinct: it uses both parents' incomes rather than just the payor's, and applies different rules for shared custody.

Imputed Income

If a parent is voluntarily underemployed or unemployed, the court can "impute" income — assign an earning capacity based on the parent's age, education, skills, work experience, and the local job market. Imputed income is used for the table lookup as if it were actual income. Common scenarios include a parent who quits a job to reduce their support obligation, takes early retirement without financial necessity, or works part-time when full-time work is available.