Who has legal standing to file a Notice of Objection to a will in Ontario?

Standing to file a Notice of Objection belongs to anyone with a genuine financial interest in how the estate is distributed — not simply anyone who disagrees with what a will says. In practice, this typically includes a beneficiary named in the will being challenged, a beneficiary under an earlier will that would apply if the current one fails, a person who would inherit under Ontario's intestacy rules if the will were set aside, and sometimes a dependant entitled to bring a support claim against the estate. A person with only a moral or emotional connection to the deceased, without a financial stake in the outcome, generally cannot file.

The court does not require you to prove your objection is correct before filing, but the registrar or another interested party can later question whether you actually have standing, and an objection can be challenged or struck out if you don't. Because the categories of who qualifies can be fact-specific — for example, whether a common-law partner or an estranged family member qualifies depends on the details of their relationship to the deceased and the estate — anyone considering filing should confirm their standing and their specific ground for objecting with a lawyer before doing so, since filing without a proper basis can expose you to cost consequences later.