Powers of Attorney Deserve As Much Attention As Your Will
February 14, 2026Can a Will Be Challenged in Ontario? A Guide on How to Avoid Litigation and Probate Disputes
In my years of practising wills and estates in Etobicoke, I continue to notice something that catches me off guard, even now.
People can come into my office with extraordinary clarity about what they don’t want.
I don’t want my sibling to see a penny of this. My son-in-law is not getting his hands on what I’ve spent a lifetime building. If any of my beneficiaries challenge my will, then they get nothing.
The feeling is vivid and the conviction is absolute. Then I ask my natural follow-up question: so what do you want to happen? Who gets the house? How do you want to divide things among your children? Is there a charity that matters to you? A grandchild you want to provide for?
And sometimes there’s a pause.
It turns out that knowing exactly who you want to exclude from your estate and knowing what you actually want for your estate are two different things. One tends to arrive with a lot of emotion behind it. The other requires sitting down and thinking it through.
Both matter, and that pause is a perfectly good reason to come talk to a lawyer. Building an estate plan around what you do want is exactly how you protect it from the people you don’t.
Which brings me to the question I get more than almost any other: how do I make sure they can’t touch it? Can my will be challenged?
The truth is that anyone can challenge anything. The better question, and the one actually worth your time, is whether a challenge would succeed. And that’s where we can do something about it.
My simple answer, which I’ll give you before you’ve even booked an appointment: make a valid will.
First, the Good News
Wills in Ontario are hard to successfully challenge. Courts don’t overturn them lightly. A will that has been properly prepared, signed, and witnessed isn’t just a piece of paper, it’s a legal document with a presumption of validity. The challenger has to knock that presumption down, and that is not easy to do.
The single most effective thing you can do to protect your estate? Make a valid will. With a lawyer. A real will, prepared with proper legal advice and signed using appropriate protocols.
You would be surprised how many estate disputes exist precisely because someone has overlooked this simple fact.
So What Grounds Can Someone Actually Use to Challenge a Will in Ontario?
There are really four main paths a challenger can take. to successfully challenge a will. Let’s walk through them, and examine how you can close each door.
1. Lack of Testamentary Capacity
To make a valid will, you have to know what you’re doing. Legally, that means you understood: the nature of making a will, the extent of what you own, who your natural heirs are, and how the will distributes your estate among them.
This is the most common ground for challenge, particularly when a will is made later in life or during an illness. The argument goes: they didn’t know what they were signing.
How you shut this down: Have a lawyer assess your capacity at the time you make the will. A good estate lawyer doesn’t just take instructions and hand you a pen, they document the conversation, ask the right questions, and create a record. If someone challenges capacity five years later, that contemporaneous record is powerful evidence. A doctor’s note around the same time doesn’t hurt either.
2. Undue Influence
The challenger claims that the will-maker was pressured, manipulated, or coerced into leaving their estate a certain way. The argument is that that the will doesn’t truly reflect their wishes, but someone else’s.
Undue influence can be notoriously difficult to prove. Even though Courts recognize that family members influence each other all the time.
How you shut this down: Meet with your lawyer alone. No spouse, no adult child, no “helpful” friend or relative in the room. A lawyer who lets a third party sit in on your will instructions is doing you no favours. When you meet independently and discuss your reasons for the decisions you’ve made, then those reasons get documented and the undue influence argument becomes very hard to sustain.
3. Formal Validity: Did You Actually Sign It Properly?
Ontario has specific requirements for a valid will. It must be in writing, signed by you, and witnessed by two people who sign in your presence and in the presence of each other. Those witnesses cannot be beneficiaries under the will (or spouses of beneficiaries).
This sounds basic. And yet wills are still challenged, and sometimes set aside, because someone didn’t follow the rules. I have seen this happen first-hand.
How you shut this down: Have a lawyer prepare and supervise the execution of your will. This is genuinely not the place to improvise.
4. Dependant’s Relief Claims
This one is different in character from the others. Under Ontario’s Succession Law Reform Act, certain dependants can make a claim against your estate if your will doesn’t provide adequate support for them.
This isn’t a challenge to the will’s validity. It’s a court saying: the will is valid, but it doesn’t do enough for the people who needed you.
How you handle this: Understand your obligations before you write someone out entirely. This doesn’t mean you can’t disinherit a competent adult child who doesn’t depend on you. It means you need advice about your specific situation before you do it. There’s often a significant difference between “I want to leave less to one child” and “I want to leave this person nothing”, and the legal implications of each can vary considerably.
Can You Prevent Someone From Challenging Your Will?
No. Anyone with standing can file a challenge, and no clause in your will, no matter how sternly worded, can take that right away. You may have seen “no-contest clauses” — provisions that say a beneficiary forfeits their share if they challenge the will. Ontario courts do not like to enforce these.
What you can do is make a challenge as unappealing and as difficult to win as possible. A will that was:
- Prepared by an experienced estate lawyer
- Executed with capacity properly assessed and documented
- Made without the presence of beneficiaries or people who stand to gain
- Accompanied by a clear record of your instructions and reasoning
This is a will that most challengers will look at and decide it isn’t worth the fight. Estate litigation is expensive, slow, and emotionally exhausting. If the grounds aren’t there, a reasonable person (and their lawyer) will think twice.
A Note on Handwritten (Holograph) Wills
Ontario does recognize holograph wills. Holograph wills are entirely handwritten and signed by you and no witnesses arenrequired. They are valid, but they are also a minefield. Courts have spent considerable time and beneficiaries have spent considerable money sorting out handwritten wills that were perfectly clear to the person who wrote them and perfectly ambiguous to everyone else.
The Bottom Line
You cannot control whether someone challenges your will. You can control how strong your wills is and how difficult it is for a challenge to succeed.
The best estate plan isn’t the cleverest one. It’s the one that was done properly, with good legal advice, from someone who took the time to understand your situation and document it well. Don’t forget to consider the value of transparency. Explaining the reasoning behind your decisions to your beneficiaries can dissuade a challenge to your will.
If your will was drafted carefully, your capacity was never in question, you weren’t being managed by anyone with a stake in the outcome, and your dependants were either provided for or legally don’t have a claim, then whoever is plotting the challenge is going to have a very hard time in court.
Richard Levitt has been helping Etobicoke families protect what they’ve built for 23 years, as part of LLDG . If you’d like to talk about your will or your estate plan, contact us here. We’re approachable, we’re local, and we’ve heard just about everything.
