Ontario law generally respects the right of competent adults to leave their estate as they choose — including to people you think are undeserving, and excluding people who expected to receive something. Unhappiness with a will is not a legal ground to challenge it.
Lack of testamentary capacity — the testator did not understand the nature of making a will, the extent of their property, or who had claims on their estate at the time they signed. Dementia, significant cognitive impairment, or confusion at the time of execution may support this ground. Capacity is assessed at the moment of signing, not before or after.
Undue influence — someone in a position of power or trust coerced or manipulated the testator into making or changing the will. This requires proof of more than persuasion; the testator's free will must have been overborne. It is difficult to prove and usually requires circumstantial evidence.
Lack of knowledge and approval — the testator did not actually know or understand the contents of the will they signed, often arising where the will was prepared by someone who benefits from it without full independent communication to the testator.
Formal defects — the will was not properly witnessed, signed, or executed in accordance with Ontario's requirements under the Succession Law Reform Act.
Fraud or forgery — the will is not genuine, or false representations induced the testator to make it.
A will challenge attacks the will's validity. A dependant support claim accepts the will as valid but argues it fails to provide adequate support. These are different legal tools, and both can be pursued simultaneously if the facts support both.
While there is no strict limitation period for will challenges, delay hurts. Evidence deteriorates, witnesses become unavailable, and estates may be distributed. Dependant support claims have a strict six-month deadline from the grant of probate. Do not wait.
This is a general overview. For advice specific to your situation, contact Sheard Law at 416-860-9990 or use our intake form.
