Estate Litigation
in Ontario
Estate disputes can arise when there are concerns about a Will's validity, undue influence, executor misconduct, or disagreements among beneficiaries. We represent clients in complex estate litigation matters before the Ontario Superior Court of Justice.
When Estate Disputes Require Court Intervention
Estate litigation is the area of law that deals with disputes arising from the administration of a deceased person's estate or the management of a trust. In Ontario, these matters proceed before the Ontario Superior Court of Justice, often by way of an application for directions—a procedure distinct from standard civil litigation.
Disputes may centre on the validity of a Will, allegations of undue influence or lack of testamentary capacity, concerns about how an Estate Trustee has managed estate assets, disagreements among beneficiaries, or claims by dependants who believe they have not been adequately provided for. These cases are governed by a combination of statutes—including the Succession Law Reform Act, the Estates Act, the Trustee Act, the Substitute Decisions Act, and the Family Law Act—alongside a significant body of common law.
At Diamond and Diamond, we represent clients in contested estate matters across Ontario. We approach every case strategically—seeking resolution through negotiation or mediation where possible, and advancing our clients' interests decisively when litigation is required.
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Call NowAreas of Estate Litigation We Handle
We represent both claimants and respondents across the full spectrum of estate disputes in Ontario.
Will Challenges
We handle disputes about the validity of a Will, including claims based on lack of testamentary capacity, undue influence, suspicious circumstances, fraud, forgery, and improper execution. Ontario's reformed legislation may save certain Wills from technical defects, but the grounds for challenge remain substantial.
Dependant Support Claims
Under Part V of the Succession Law Reform Act, spouses, common-law partners, children, parents, and siblings who were financially dependent on the deceased may claim support from the estate. These claims must generally be filed within six months of probate being granted.
Executor and Trustee Disputes
We represent beneficiaries seeking to hold Estate Trustees accountable for misconduct, delay, or mismanagement—and we represent Estate Trustees who need to defend their administration. This includes applications to compel an accounting, reduce compensation, or remove and replace a trustee.
Power of Attorney Litigation
Disputes over Powers of Attorney—including allegations that an Attorney for Property has mismanaged assets, breached their fiduciary duty, or acted outside their authority—are increasingly common. We assist families in protecting incapable persons from financial exploitation.
Passing of Accounts
We represent both Estate Trustees seeking court approval of their accounts and beneficiaries who wish to challenge those accounts. This includes disputes over compensation, unexplained transactions, and allegations of breach of fiduciary duty.
Trust Disputes
We handle disputes involving inter vivos (living) trusts, testamentary trusts, and resulting or constructive trust claims. These cases often involve allegations of unjust enrichment, breach of trust, or disagreements about the proper interpretation of trust terms.
Contested Guardianship
When family members disagree about who should serve as guardian for a person who has lost capacity, or when an existing guardianship arrangement is challenged, we represent clients in proceedings under the Substitute Decisions Act.
Spousal Election Claims
A surviving married spouse in Ontario has the right to elect to receive their entitlement under the Family Law Act rather than what was left to them in the Will. This election must be made within six months of death and can significantly alter the distribution of the estate.
Common Grounds for Challenging a Will in Ontario
A Will challenge is one of the most common forms of estate litigation. Ontario law recognizes several grounds on which a Will may be contested.
Lack of Testamentary Capacity
The testator did not understand the nature and effect of making a Will, the extent of their property, or the claims of persons who would normally expect to benefit.
Undue Influence
Someone exerted pressure or control over the testator, overriding their free will and causing the Will to reflect the influencer's wishes rather than the testator's own intentions.
Suspicious Circumstances
Circumstances surrounding the Will's preparation or execution raise doubt—such as a sudden change in beneficiaries, involvement of a beneficiary in drafting the Will, or secrecy.
Improper Execution
The Will was not signed or witnessed in accordance with Ontario's formal requirements. While recent legislative reforms may save some improperly executed Wills, defects in execution remain a basis for challenge.
Protecting Those Who Were Left Behind
Under Part V of the Succession Law Reform Act, certain individuals who were financially dependent on the deceased can apply to the court for support from the estate if they were not adequately provided for—whether through the Will or under Ontario's intestacy rules.
A dependant may include a spouse (including a common-law partner who cohabited for at least three years), a former spouse, a parent, a child (including an adult child who remained financially dependent), or a sibling. The claim must generally be filed within six months of the Certificate of Appointment of Estate Trustee being issued.
The court considers the dependant's financial needs, the size of the estate, the dependant's contributions to the deceased, existing support obligations, and any agreements between the parties. If the court finds that adequate support was not provided, it has broad discretion to order a redistribution of the estate—including lump sum payments, periodic support, or transfers of property.
Key Considerations
- Dependant support claims are separate from inheritance—you can bring a claim even if you are named as a beneficiary
- These claims can reach assets that would otherwise pass outside the estate, such as jointly held property or insurance proceeds
- The six-month limitation period is strictly enforced, though the court may allow a late claim against undistributed assets
- Estate Trustees should not distribute the estate within the first six months if a dependant support claim is possible
- Courts may consider both legal and moral obligations the deceased owed to the dependant
- Blended families, common-law relationships, and adult children who remained dependent are increasingly common sources of claims
Strategic, Practical, and Decisive
Negotiation and Mediation
Estate disputes are inherently personal. They involve families, grief, and deeply held expectations. Wherever possible, we seek to resolve matters through negotiation or mediation—approaches that can preserve relationships, reduce costs, and reach outcomes more quickly than a trial.
Ontario's estate mediation process, which can be initiated under the Rules of Civil Procedure, provides a structured forum for parties to explore settlement with the assistance of a neutral mediator. Many estate disputes—including will challenges, beneficiary disputes, and compensation disagreements—are resolved at mediation without the need for a court hearing.
Litigation When Required
When negotiation is not possible—or when the opposing party is not acting in good faith—we advance our clients' interests decisively in court. We have experience handling contested applications, motions, and hearings before the Ontario Superior Court of Justice.
Estate litigation in Ontario often proceeds by way of application rather than action, which means the rules and procedures differ from standard civil litigation. Having a legal team that understands these distinctions—and the unique costs rules that apply to estate matters—is essential to achieving a favourable outcome.
Need a strategic approach to an estate dispute?
Speak to a LawyerLimitation Periods in Estate Litigation
Estate litigation is governed by strict deadlines. Missing a limitation period can result in the permanent loss of your legal rights. Act early.
6 Months
Dependant support claims must be filed within six months of the Certificate of Appointment of Estate Trustee being issued.
6 Months
A surviving married spouse must elect to take under the Family Law Act within six months of the deceased's death.
2 Years (General)
The general limitation period under Ontario's Limitations Act is two years from the date a claim is discovered—but this does not apply to all estate claims.
No Fixed Limit
Will challenges and objections to accounts are not subject to the standard two-year limitation period, but delay can still prejudice your claim.
Estate Litigation FAQs
Common questions about estate disputes in Ontario.
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