Can I legally leave a child out of my will in Ontario?

In Ontario, testamentary freedom — the right to leave your estate to whoever you choose — is a fundamental principle, but it has limits when it comes to dependants. You can generally disinherit an adult, self-sufficient child in your will, but a child who was financially dependent on you at the time of your death may have a legal claim against your estate under Ontario's dependant support provisions.

The Succession Law Reform Act allows certain dependants — including your children regardless of age, if they were dependent on you — to apply to court for support from your estate. A court will consider the size of your estate, the child's needs, and other circumstances. The claim does not automatically succeed, but it can reduce or override what you left (or did not leave) in the will.

A minor child cannot be fully disinherited in practice. An adult child who is self-supporting and has not relied on you financially is in a much weaker position to make a dependant support claim.

If you are intentionally disinheriting a child, the reasons should ideally be documented (a lawyer can help), and you should understand that the decision may be challenged. Speaking with a lawyer before finalizing such a will is strongly advisable.