Rule 503.Primary support need

The share. Each parent's net available income is expressed as a percentage of the parents' combined net available income — their Primary Share — so the children's needs and extraordinary medical costs are allocated in proportion to ability to pay. Where the person seeking support is not a parent, the obligor's share is 50%.

The need. Each parent's primary support obligation is their share multiplied by the total of the elements of the children's primary support need.

Allowances. The primary allowance has a per household component — 25% of the self support allowance minus $25 — and a per child component, 25% of the self support allowance plus $20, each rounded to the nearest multiple of 10, with half-child allowances rounded to a multiple of 5. A household's allowance is the number of children times the per child figure, plus the per household component. The figures are adjusted each January.

The two-part structure reflects how households actually cost money: a second child adds less than the first, because the roof over them is already paid for.

Child care. All costs of caring for and supervising the children that either parent needs in order to work are shared. No hypothetical or attributed costs are permitted — the expense must be real. Cancelled cheques, child care contracts, receipts and other business records are admissible alongside testimony.

Health insurance. Where a party pays premiums covering the children of the union, three-quarters of their out-of-pocket premium is included as primary support — or one-half where they have other minor children to support. Premiums paid by a guardian or through a stepparent may count, but not where the policy also covers the guardian's or stepparent's own children.

Private school. Included as a primary expense only where the parties have adequate financial resources AND the general equities support it — considering whether the parents previously agreed to private schooling, whether the child has special needs a public school cannot accommodate, or whether the family's history indicates the child would likely have attended but for the separation.

Both conditions, in that order. A court will not put a family into debt for tuition, and will not treat the separation as a reason to end a schooling the child would otherwise have had.

Shared equal placement. Established by court order, written agreement, or other evidence in the absence of either, at 164 or more overnights annually in each household. Each child is counted as one half in each household, and the court sets additional primary support allowances to accommodate that split. Changing an order between primary and shared equal placement must be proven by order or written agreement, or by clear and convincing evidence.

Shared incidental expenses. Where a parent is not contributing equally to them, the court may impose any appropriate sanction — including recalculating support as though the child lived primarily with the other parent. Whether an expense counts depends on the totality of the circumstances: whether the parents agreed or acquiesced to it even without agreeing how to split it, whether similar families customarily incur it, whether both parents benefit, its size and frequency, and each parent's ability to contribute.

Presumptively included are haircuts, school lunches, instrument rentals, school supplies, school project supplies, enrolment, uniform and other mandatory fees for local recreational sports or extracurricular activities (though not equipment), and local field trips that need no overnight stay or air travel. An action to enforce this must be pleaded with particularity.

That list is doing something valuable: it settles, in advance, arguments that otherwise recur monthly for years.

Small orders. Where all the minor children are in shared placement and the calculation produces a net order of less than $50 a month, no affirmative current support is ordered. And either parent may be assessed an obligation regardless of who filed.