When does child support end? Adult children, university, disability and how to stop paying properly

Your child is about to turn 18, or has already. Perhaps they are heading to college, perhaps they have moved out, perhaps they are living at home and not doing much of anything. Whether you pay support or receive it, the question is the same: when does this end, and who decides?

The honest answer is that in both Canada and the US, support ends when the law says the child is no longer dependent, not when a birthday arrives, and the paperwork has to catch up with reality before payments can stop. This guide walks through the Canadian rules, the main US patterns, and the steps that end support cleanly. It is general information, and the details vary by province and state, so confirm your own situation with a lawyer or a family law information centre.

Canada: it ends when the child stops being a "child of the marriage"

For married or divorced parents, the Divorce Act defines a "child of the marriage" as a child of two spouses or former spouses who, at the material time, "is under the age of majority and who has not withdrawn from their charge", or who "is the age of majority or over and under their charge but unable, by reason of illness, disability or other cause, to withdraw from their charge or to obtain the necessaries of life."

Two things follow. First, a child under the age of majority who still lives with a parent is almost always a child of the marriage. Second, an adult child can remain one if an "other cause" keeps them dependent. Justice Canada's Guidelines guide says plainly: "In many cases, courts consider the pursuit of reasonable post-secondary education to be a valid 'other cause'." It adds: "Remember, your obligation to support your children financially does not automatically end because they have reached the age of majority."

Provincial family law uses similar tests for unmarried parents. Ontario's rules, as explained by Steps to Justice, say a child stops being a dependant if they marry, or if they are at least 16 and voluntarily withdraw from parental control. The withdrawal must be voluntary; a child who is pushed out does not lose support on that basis. A child 18 or older can still be a dependant if they cannot support themselves because of illness or disability, or because they are in full-time school.

Age of majority differs by province

The Divorce Act takes the age of majority from the province where the child habitually lives. According to Justice Canada, it is 18 in Alberta, Manitoba, Ontario, Prince Edward Island, Quebec and Saskatchewan, and 19 in British Columbia, New Brunswick, Newfoundland and Labrador, the Northwest Territories, Nova Scotia, Nunavut and Yukon. For a child living outside Canada it is presumed to be 18.

What usually keeps support going past the age of majority

• Full-time post-secondary study. College, university, a trade program or an apprenticeship. Courts look at whether the plan is reasonable for this child and this family. A first degree or diploma is the typical end point, though there is no fixed rule in the Guidelines, and a second degree is sometimes supported where the family would have paid for it had they stayed together.
• Illness or disability. A child who cannot support themselves because of a physical or mental health condition can remain a child of the marriage indefinitely. FairWell's guide to parenting plans for children with special needs covers how to write this into an agreement.
• A gap or transition. A child who finishes high school in June and starts a program in September is usually still dependent over the summer.

What usually ends it: the child is working full time and self-supporting, has married, has left home on their own terms, or has finished the education the parents are expected to help with. If a child drops out, takes a year off with no plan, or refuses all contact with the paying parent while demanding money, the answer is less certain and depends on the facts. These are the cases to get advice on.

The amount can change for an adult child

Section 3(2) of the Federal Child Support Guidelines gives two options for a child at or over the age of majority. The default is the amount "determined by applying these Guidelines as if the child were under the age of majority", in other words the ordinary table amount. But if the court "considers that approach to be inappropriate", it can set "the amount that it considers appropriate, having regard to the condition, means, needs and other circumstances of the child and the financial ability of each spouse to contribute to the support of the child."

In practice this is where a student's own income, scholarships, bursaries, student loans and summer earnings come in. A student living away at school often receives a budget-based amount rather than the table figure, with tuition, residence and books handled as section 7 expenses shared between the parents in proportion to income after the child's own contribution is deducted. Our guide to section 7 expenses explains that calculation, and the FairWell calculators can run the numbers. If you have an RESP, see RESPs and 529 plans at separation.

Never stop on your own

This is the point that catches the most people. An order, or an agreement filed with a court or registered with an enforcement program, keeps running until it is changed, even if your child is now 22, working, and living in another city. Steps to Justice puts it this way for Ontario: even if your agreement or order sets an end date, "the responsibility to pay child support usually continues for as long as your child is a dependant", and when it does end you "have to take steps to make sure the separation agreement or court order is no longer being enforced."

If you simply stop, the enforcement program (the Family Responsibility Office in Ontario, the Maintenance Enforcement Program in several other provinces, the Family Maintenance Enforcement Program in BC) continues to record the amount as owing. Those months become arrears, which can lead to garnished wages, a suspended driver's licence or passport, and interest. Arrears are hard to cancel after the fact. Our guide on enforcement when a parent does not pay shows how far these powers reach.

How to end child support properly in Canada

1. Read your order or agreement

Many agreements include a termination clause: for example, support ends when the child turns 18 and is no longer in full-time attendance at an educational institution, or at a set age such as 22 or 25. Some say support for each child ends "on the occurrence of a terminating event" and list them. Some say nothing. What the document says tells you whether you need a new document or just a notice.

2. Talk to the other parent early

Start the conversation six months before the expected end, not the week after. Most disagreements about adult children are about information: what is the child actually doing, what does the program cost, what are they earning. Share the facts and ask for theirs.

3. Put the change in writing

If you agree, sign a short amending agreement that says what ends, when, and what happens to any shared expenses. Each of you should get independent legal advice if the original agreement had it. If the original was filed with the court or an enforcement program, file the amendment the same way, or you will have an agreement the program cannot see.

4. Notify the enforcement program

Each program has its own form to end or change enforcement, and most require either both parents' consent or a new court order. Steps to Justice notes that in Ontario, once a child is no longer a dependant, you may need to contact the FRO, and otherwise bring a motion to change the order. Do not assume the program will stop automatically because a date in the order has passed.

5. If you cannot agree, apply to vary

Section 14 of the Guidelines sets out what counts as a change of circumstances for a variation. Where the order is based on the table, any change that "would result in a different child support order" qualifies, and a child ceasing to be a child of the marriage is one. Where it is a non-table amount, "any change in the condition, means, needs or other circumstances" of a spouse or child qualifies. Bring the evidence: the child's enrolment status or completion letter, their income, where they live. Our guide to changing an agreement when circumstances change covers the process.

6. Keep paying until it is changed

Until the amendment is signed and filed, or the court varies the order, pay what the order says. If you believe support has clearly ended, you can ask the other parent to agree in writing that payments after a certain date are held as a credit against any later finding. Get advice before relying on that.

The United States: the age is set state by state

There is no federal rule. Each state sets the age at which support ends, the events that end it earlier (often called emancipation), and whether it can run longer for education or disability. A few examples from official court and law library sources show the range:

• California. The court self-help centre says the duty "typically ends when a child turns 18 and graduates high school", or when a full-time high school student turns 19, whichever happens first. It also ends if the child marries, enters a domestic partnership, joins the military, is emancipated or dies. Support "can continue after a child turns 18 (or 19) if the child is disabled and can't support themselves", or if the parents agree.
• Texas. The State Law Library notes that court-ordered support ends in several circumstances, "including when the child turns 18 or graduates from high school", under sections 154.001 and 154.002 of the Family Code, with separate rules for a disabled child.
• New York. The state court system states: "In New York State, a child is entitled to be supported by his or her parents until the age of 21." A younger child may be treated as emancipated if they marry, become self-supporting, join the military, or leave home and refuse to obey reasonable parental commands.
• Massachusetts. Under General Laws chapter 208, section 28, a court may order support for a child aged 18 to 20 who lives with a parent and is "principally dependent upon said parent for maintenance", and for a child aged 21 to 22 who is dependent "due to the enrollment of such child in an educational program", excluding costs beyond an undergraduate degree. The 2025 guidelines cap post-secondary contributions so that no parent is ordered to pay more than 50 percent of the cost.

Three points carry across states. Support enforced by a child support agency does not stop by itself; you have to request termination or a modification. With several children on one order, the total usually does not drop automatically when the eldest ages out; it has to be recalculated. And college costs vary widely: some states allow courts to order a contribution, some do not, and many families settle it in the divorce agreement. FairWell's guide to child support in the US has more on the state frameworks.

What to say to your child

Children in their late teens often know more about the support fight than parents think, and the message they can absorb is "you are being argued over". Keep them out of it. Do not ask a 19 year old to tell the other parent to keep paying, and do not tell them their tuition depends on whether the other parent "comes through". If they are an adult student, it is reasonable to ask them for their course registration and fee statements, because both parents and the court need them. That is paperwork, not a loyalty test.

Common mistakes

• Stopping on the 18th birthday without checking the order, then facing arrears and enforcement.
• Agreeing verbally to end or reduce support and never filing anything.
• Assuming a child living away at university costs the same as one at home. The Guidelines allow a different approach for adult children; use it.
• Forgetting that section 7 expenses can continue after table support ends, or vice versa.

If your agreement has no end-of-support clause, this is a good moment to add one. The FairWell separation agreement builder includes termination and review clauses for child support, and the professional directory lists family lawyers and mediators by province and state who can review what you have drafted.

Sources

1. Divorce Act, section 2, definitions of "child of the marriage" and "age of majority" (Justice Laws Website, Government of Canada)
2. The Federal Child Support Guidelines: Step-by-Step, Step 2 (Department of Justice Canada)
3. Federal Child Support Guidelines, SOR/97-175, sections 3 and 14 (Justice Laws Website, Government of Canada)
4. When does child support end? How do I end it? (Steps to Justice, CLEO)
5. Child support (California Courts Self-Help Guide)
6. Child Support, Texas Family Code sections 154.001 and 154.002 (Texas State Law Library)
7. Until What Age Is a Parent Obligated to Support a Child? (New York State Unified Court System)
8. Massachusetts law about child support over age 18 (Mass.gov, Trial Court Law Libraries)

This guide is general information for parents, not medical, psychological or legal advice. It draws on published research and guidance from recognised health and family justice bodies, listed under Sources. Every child and family is different. If you are worried about your child or yourself, talk to your family doctor or a qualified professional. FairWell can help you find one through the professional directory. How we write and check our guides.