A divorce ends a valid marriage based on something that happened after the marriage — in Ontario, almost always one year of separation. An annulment (a declaration of nullity) instead says the marriage was never legally valid at all, due to a defect that existed at the time it took place, such as a prior undissolved marriage, lack of valid consent, or fraud going to the nature of the marriage itself. Annulments are governed by Ontario’s Annulment of Marriages Act and are granted far less often than divorces, since the grounds are specific and narrow.
- A divorce ends a valid marriage; an annulment declares the marriage was never valid to begin with.
- The overwhelming majority of Ontario marriage endings proceed as a divorce, typically after one year of separation.
- Annulment grounds are narrow — commonly bigamy, lack of valid consent, or specific forms of fraud going to the marriage itself.
- A civil annulment does not dissolve a religious marriage — a separate religious process may still be needed.
- Property and support issues can still arise even where a marriage is annulled, depending on the circumstances.
- Given how narrow the grounds are, most people who think they want an annulment are actually better served by a straightforward divorce.
The Core Difference
The distinction between an annulment and a divorce comes down to timing and legal theory. A divorce ends a marriage that was valid when it happened, based on something that occurred after the marriage — overwhelmingly, separation for at least one year. An annulment, formally a declaration of nullity, instead says the marriage was never legally valid at all, because of a defect that existed at the time the marriage took place.
Grounds for an Annulment
Ontario’s Annulment of Marriages Act governs civil annulments, and the available grounds are specific rather than a broad, modern list. Commonly cited grounds include a party already being validly married to someone else at the time (bigamy), lack of valid consent to the marriage (including consent obtained through duress or certain kinds of deception), and specific capacity issues. These grounds are narrower than many people assume.
A marriage that breaks down quickly, or that one party regrets, is not itself grounds for annulment — no matter how short the marriage was. Annulment requires a specific legal defect that existed at the time of the marriage, not dissatisfaction afterward.
Grounds for a Divorce
Divorce in Canada is governed by the federal Divorce Act. The overwhelming majority of Ontario divorces — by most estimates, the large majority — proceed on the ground of one year’s separation, rather than the fault-based grounds of adultery or cruelty, which remain legally available but are rarely used in practice given the added cost, time, and conflict they typically bring. See our guide on how to file for divorce in Ontario for the practical steps.
Why Annulments Are Rare
Because the grounds are narrow and fact-specific, and because proving a defect existing at the time of the marriage is often more demanding than establishing a year of separation, annulments are granted far less often than divorces in Ontario. For most people whose marriage has broken down, a straightforward divorce — not an annulment — is both the realistic and the appropriate path.
If you believe you have genuine annulment grounds — for example, discovering your spouse was already married to someone else — get advice early. These cases often require specific evidence that is easier to gather close to the time the issue is discovered.
Religious Annulment Is a Separate Process
A religious annulment — for example, a Catholic declaration of nullity — operates entirely within that faith community’s own rules and has no legal effect on your marital status under Canadian law. Someone with a religious annulment remains legally married in Ontario until they separately obtain a civil divorce or civil declaration of nullity.
Which One Applies to You
If you are unsure whether your situation might support a genuine annulment, or whether divorce is the right (and more realistic) path, get advice before filing anything. The forms, evidence, and legal tests involved are different between the two processes, and starting down the wrong one can cost real time and money.
Not sure whether you need an annulment or a divorce in Toronto or the GTA? Call 416-274-2222 for a free, confidential consultation.
Frequently Asked Questions
No — generally the opposite. A divorce based on one year of separation is a well-established, relatively straightforward process. An annulment requires proving a specific legal defect existed at the time of the marriage, which is a narrower and often more demanding case to make.
No. The length of a marriage, or the fact that it quickly broke down, is not itself a ground for annulment. Annulment requires a specific defect — such as a prior undissolved marriage, lack of valid consent, or certain forms of fraud — that existed when the marriage took place.
Not necessarily. Depending on the circumstances and how long the parties lived together, property and support issues can still be addressed, sometimes under different legal provisions than apply to a straightforward divorce. Get advice specific to your situation.
Ontario’s Annulment of Marriages Act governs civil annulments provincially, while divorce is governed by the federal Divorce Act. The two operate under different statutes with different tests.
No. A religious annulment is a separate process within your faith community and has no effect on your legal marital status in Canada. You remain legally married until you obtain a civil divorce or a civil declaration of nullity.
Certain kinds of fraud can be grounds, but generally only fraud going to the essential nature of the marriage itself — not, for example, a spouse lying about their finances or personality after the fact. The bar for fraud-based annulment is narrow and fact-specific.