Changing a Child or Spousal Support Order or Agreement

Can Support Really Be Changed?

Yes. A child support or spousal support order — or the support terms in a separation agreement — is not necessarily fixed forever. Incomes rise and fall, parenting schedules shift, children grow up, and spouses' circumstances change in ways that can genuinely affect what a fair support amount looks like. Ontario's system generally allows support to be revisited when circumstances have changed enough to justify it, rather than requiring everyone to live indefinitely with terms that no longer fit their situation.

That said, support generally cannot simply be changed unilaterally by one person deciding the old amount no longer makes sense. Until a new agreement is signed, or a court changes an order, the existing support obligation generally continues to apply and remains enforceable.

This page is deliberately narrow. Rather than repeating the general rules for changing any family court order, it focuses on the question people searching for it usually have first: what actually counts as a change big enough to matter, specifically for child or spousal support.

The Material Change Test, Briefly

Where support was set out in a court order, changing it generally requires showing what is often called a material change in circumstances — a change that is significant, and that was not already known or accounted for when the existing order was made. This is the same general legal test used for changing parenting time and decision-making orders, and the mechanics of actually bringing that request to court — the motion to change process, required forms, and timelines — are covered in detail on our page about changing or enforcing a family court order. This page focuses specifically on what that test tends to look like when the issue is support.

One general principle worth knowing up front: the person asking for the change generally carries the burden of showing that a material change has actually occurred. A court is generally not expected to simply take that assertion at face value — it typically wants to see what has changed, since when, and why it was not already reflected in the existing order or agreement.

What Counts as a Material Change for Child Support

Child support in Ontario is generally based on the paying parent's income, the number of children, the parenting arrangement, and sometimes special or extraordinary expenses. When one of these genuinely shifts, it can potentially support a change. See also our companion article on whether child support can change over time. Commonly discussed examples include:

• A significant, lasting change in either parent's income — a job loss, a new job, a substantial raise, or a return to work after time away, for example. A short-term or minor fluctuation is generally less likely to qualify than a change that appears lasting.
• A change in the parenting time arrangement actually being followed — for instance, moving from one parent having the child most of the time into a shared-parenting arrangement, or the reverse. Because child support calculations generally depend in part on the parenting schedule, a genuine shift here can affect the appropriate amount.
• A child's needs changing — for example, new or different special or extraordinary expenses such as childcare, health-related costs, or education costs, or a child's needs decreasing.
• A child reaching the age of majority or finishing school — under the Divorce Act, a child does not automatically stop being a "child of the marriage" simply by turning 18, particularly if they remain in full-time school or cannot support themselves for another recognized reason. Whether support should change, and by how much, generally depends on the specific facts — see support for adult children for more detail.

These are general, commonly recognized categories rather than a guaranteed list — whether a specific situation qualifies as material generally depends on what the existing order or agreement was actually based on, and how significant the change genuinely is. Where the parenting time change is significant enough to affect which set of Guidelines rules applies — for example, crossing into or out of a shared-parenting situation — the resulting recalculation can be more involved than a straightforward income update, which is part of why formalizing any real change in parenting time properly generally matters.

What Counts as a Material Change for Spousal Support

Spousal support tends to raise somewhat different considerations than child support, because it often depends on the reasons support was ordered in the first place — compensating a spouse for the marriage's economic impact, meeting genuine need, or some combination. Commonly discussed examples of a potential material change include:

• A significant change in either spouse's income, similar in concept to child support, though how much it matters can depend on why support was originally ordered.
• Retirement by the paying spouse — generally recognized as a potential material change where it meaningfully reduces income, though a court will generally still look at whether the retirement is reasonable in the circumstances, and at both spouses' ongoing means and needs.
• Health changes affecting either spouse's ability to work or to become self-sufficient, which can potentially support either an increase or a decrease depending on whose health has changed.
• The recipient repartnering or remarrying — this is a commonly discussed factor and can lead to a review of spousal support, but it is not an automatic or bright-line rule that support simply ends. Outcomes are generally fact-dependent, and courts have generally treated this differently depending on whether the support was more need-based or more tied to compensating for the marriage itself.

Because spousal support entitlement and amount can rest on more varied reasoning than child support, professional guidance before assuming any of the above will change your situation is generally worthwhile.

Changing Support by Mutual Agreement

Court is not always required. If child or spousal support was set out only in a private separation agreement that was never filed with the court, both people can generally change it simply by signing a new agreement reflecting the updated terms — no court application is generally needed for that step alone. See changing a separation agreement for more detail on how that generally works.

Where support was instead set out in a court order — or in an agreement that was filed with the court so it could be enforced — both people agreeing on a change generally still means putting that agreement before the court in some form, so a new order reflects it. The practical difference is usually that an unopposed, consent-based request can generally move through the court process more quickly and simply than a contested one, since there is no dispute for a judge to resolve.

Changing Support Through Court

When people cannot agree, either side can generally ask a court to change an existing support order through a motion to change, generally supported by evidence of the material change relied on, such as updated financial disclosure for an income-based change. The general mechanics of this process — where it is filed, what documents are typically involved, and how a contested motion is generally resolved — are covered on our page about changing or enforcing a family court order, since the same process applies whether the underlying dispute is about support, parenting time, or decision-making responsibility.

Until a court actually grants a new order, the existing support order generally continues to apply and generally remains enforceable through the Family Responsibility Office, even if a motion to change it is already underway.

Does a Parenting Time Change Automatically Change Support?

No, generally not automatically. Even where parents genuinely start following a different schedule than what an order or agreement describes — for example, drifting into a roughly shared-parenting arrangement — the support amount does not update on its own simply because the day-to-day reality changed. Because child support calculations generally take the parenting arrangement into account, a real shift here can be a valid basis for a change, but it generally still needs to be formalized through a new agreement or a court variation before it legally applies. Continuing to pay, or accepting, an outdated amount after a real schedule change can create complications later, so addressing it sooner is generally preferable to waiting.

Common Mistakes

• Assuming a temporary income dip automatically qualifies as a material change
• Unilaterally reducing or stopping payments before any new agreement or order exists
• Assuming a child turning 18 automatically ends support without checking the facts
• Assuming an ex's new relationship automatically ends spousal support
• Not updating paperwork after parenting time genuinely changes
• Waiting years to address a change, letting arrears or overpayments build up
• Confusing an unfiled private agreement with a filed, court-enforceable order

Frequently Asked Questions