Adultery is a legal ground for divorce in Ontario under the federal Divorce Act, R.S.C. 1985, c. 3, s. 8, but it has virtually no impact on property division, spousal support, or parenting arrangements. Over 95% of Ontario divorces proceed on the one-year separation ground rather than adultery because Canada operates a no-fault divorce system. While proving your spouse's infidelity can eliminate the one-year waiting period, the emotional cost, evidentiary burden, and additional legal fees rarely justify this approach. The cheating spouse remains entitled to an equal share of net family property, full consideration for spousal support, and parenting time based solely on the children's best interests.
| Key Facts | Ontario Adultery Divorce |
|---|---|
| Filing Fee | $669 total ($224 application + $445 set-down) |
| Waiting Period | None if adultery proven; 1 year for separation-based |
| Residency Requirement | Either spouse must live in Ontario for 1 year before filing |
| Grounds for Divorce | Adultery, Cruelty, or 1-Year Separation |
| Property Division Type | Equalization of Net Family Property (no-fault) |
| Impact on Support | None under Divorce Act, s. 15.2(5) |
| Impact on Property | None unless financial misconduct occurred |
| Impact on Parenting | None; best interests of child governs |
| Condonation Bar | Must separate within 90 days of learning of affair |
| Evidence Standard | Balance of probabilities (civil standard) |
What Is Adultery Under Ontario Divorce Law?
Adultery in Ontario requires voluntary sexual intercourse between a married person and someone other than their spouse. Under the Divorce Act, R.S.C. 1985, c. 3, s. 8(2)(b)(i), adultery constitutes marriage breakdown and provides immediate grounds for divorce without any waiting period. A single act of sexual intercourse with a third party is sufficient to establish adultery; the duration of the affair is irrelevant. The person who committed the adultery cannot use their own infidelity as grounds for divorce—only the innocent spouse may rely on this ground.
The definition of adultery in Canadian law is narrow and specific. Emotional affairs, online relationships, sexting, or other intimate conduct short of sexual intercourse do not legally constitute adultery. Same-sex sexual activity with a third party does qualify as adultery following the Civil Marriage Act of 2005. The third party does not need to be named in court documents, though identifying them may strengthen the evidence.
Ontario courts require more than suspicion or opportunity to prove adultery. The spouse alleging infidelity must demonstrate on a balance of probabilities—meaning more likely than not—that sexual intercourse occurred. Acceptable evidence includes:
- Sworn affidavit from the cheating spouse admitting the affair
- Testimony from the third party confirming the relationship
- Text messages, emails, or other written communications indicating sexual activity
- Photographs or videos (legally obtained)
- Witness testimony regarding circumstances strongly suggesting adultery
- Private investigator reports documenting suspicious behavior
Circumstantial evidence can establish adultery, but it must be strong enough to support a reasonable inference that sexual intercourse occurred. Evidence of opportunity alone—such as hotel receipts or late nights—is insufficient without additional proof.
Does Adultery Affect Property Division in Ontario?
Adultery has no impact on property division in Ontario divorces. The Family Law Act, R.S.O. 1990, c. F.3, s. 5 establishes an equalization framework that divides net family property without regard to marital misconduct. The spouse with the higher net family property pays half the difference to the other spouse, regardless of who caused the marriage breakdown through infidelity. This no-fault approach means the cheating spouse receives their full equalization entitlement.
Ontario's equalization system operates mechanically: each spouse calculates their Net Family Property (NFP) by subtracting the value of assets owned at marriage and excluded property from the value of assets owned at separation. The spouse with the higher NFP owes the other spouse half the difference. Adultery does not factor into this calculation.
| Property Division Comparison | With Adultery | Without Adultery |
|---|---|---|
| Calculation Method | NFP Equalization | NFP Equalization |
| Division Standard | 50/50 of difference | 50/50 of difference |
| Excluded Property | Same rules apply | Same rules apply |
| Matrimonial Home | Equal rights | Equal rights |
| Pension Division | Equal division | Equal division |
| Impact of Fault | None | None |
The Ontario Court of Appeal has confirmed that conduct, including adultery, is irrelevant to property division. Only the financial consequences of conduct may be considered. The sole exception involves financial misconduct directly related to the affair—such as spending $50,000 on gifts for an affair partner or depleting retirement accounts to fund a secret relationship. In such cases, the court may adjust equalization to account for the dissipation of assets, but this addresses the financial harm, not the adultery itself.
To succeed on a claim of unconscionable depletion under Family Law Act, s. 5(6), the innocent spouse must prove:
- Significant marital funds were spent on the extramarital relationship
- The spending was reckless or intentional
- The depletion rises to the level of unconscionability
- The conduct resulted in measurable financial harm
This is a high threshold. Courts rarely adjust equalization based on affair-related spending unless the amounts are substantial and the conduct egregious.
Does Adultery Affect Spousal Support in Ontario?
Adultery has no impact on spousal support entitlement or calculation in Ontario. The Divorce Act, R.S.C. 1985, c. 3, s. 15.2(5) explicitly prohibits courts from considering marital misconduct when determining spousal support. This provision states that "the court shall not take into consideration any misconduct of a spouse in relation to the marriage." The cheating spouse remains fully entitled to spousal support if they meet the criteria for entitlement.
Ontario courts determine spousal support using the Spousal Support Advisory Guidelines (SSAG), which calculate support based on income difference, marriage length, and presence of dependent children. Under the without-child-support formula, support ranges from 1.5% to 2.0% of the gross income difference multiplied by years of marriage, capped at 37.5% to 50% of the income gap after 25 years.
The Family Law Act, s. 33(10) contains a narrow exception allowing courts to consider conduct that is "so unconscionable as to constitute an obvious and gross repudiation of the relationship." However, adultery alone almost never meets this threshold. Courts have consistently held that infidelity, while hurtful, does not rise to the level of unconscionable conduct that would affect support obligations.
| Spousal Support Factor | Impact of Adultery |
|---|---|
| Entitlement | None |
| Amount Calculation | None |
| Duration | None |
| Compensatory Support | None |
| Non-Compensatory Support | None |
| Needs-Based Support | None |
The policy rationale for this rule is clear: support obligations arise from the economic consequences of the marriage and its breakdown, not from moral judgments about marital conduct. A spouse who sacrificed career advancement to raise children remains economically disadvantaged regardless of who committed adultery.
Does Adultery Affect Parenting Arrangements in Ontario?
Adultery has no direct impact on parenting arrangements in Ontario. The Divorce Act, R.S.C. 1985, c. 3, s. 16 requires courts to determine decision-making responsibility and parenting time based solely on the best interests of the child. The 2021 amendments to the Divorce Act replaced the terms "custody" and "access" with "decision-making responsibility" and "parenting time" to emphasize the child-centered nature of these determinations.
The best interests of the child analysis under Divorce Act, s. 16(3) considers:
- The child's physical, emotional, and psychological needs
- The child's relationship with each parent and other family members
- Each parent's willingness to support the child's relationship with the other parent
- The history of care for the child
- The child's cultural, linguistic, and spiritual heritage
- The child's views and preferences, considering age and maturity
- Family violence history and its impact on parenting capacity
Adultery is not a listed factor. A parent's infidelity does not indicate poor parenting ability, and Ontario courts consistently refuse to punish adulterous parents by reducing their parenting time. The court in Bressi v. Skinulis confirmed there is no presumption favoring equal parenting time—schedules are determined case-by-case based on the child's needs.
The only circumstance where adultery might tangentially affect parenting arrangements is when the affair partner poses a safety risk to children or when the adulterous parent's conduct demonstrates poor judgment that could affect parenting capacity. Even then, the focus remains on the child's welfare, not punishment for infidelity.
Should You File for Divorce Based on Adultery in Ontario?
Filing for divorce based on adultery rather than one-year separation is rarely advisable in Ontario. While adultery eliminates the waiting period, the practical disadvantages typically outweigh this benefit. Over 95% of Ontario divorces proceed on the separation ground because it requires no evidence of fault, reduces conflict, and achieves the same outcome.
| Ground for Divorce | Waiting Period | Evidence Required | Typical Cost | Conflict Level |
|---|---|---|---|---|
| One-Year Separation | 1 year | Separation date only | $669-$2,000 | Low |
| Adultery | None | Substantial proof | $5,000-$15,000+ | High |
| Cruelty | None | Substantial proof | $5,000-$15,000+ | High |
Consider filing on adultery grounds only if:
- Your spouse admits the affair in a sworn affidavit, eliminating the evidentiary burden
- You have urgent reasons to finalize the divorce quickly (such as remarriage plans)
- You have already separated and simply need to choose between grounds
- The one-year separation period would create genuine hardship
Remember that you can file for divorce at any time after separation and simply wait for the one-year period to expire. Many couples file immediately and let the case proceed through the court system while the separation period runs. This often results in similar timing without the burden of proving fault.
Proving Adultery in Ontario Court: Evidence Requirements
Proving adultery in Ontario court requires meeting the civil standard of proof: balance of probabilities. This means demonstrating that adultery more likely than not occurred. While this standard is lower than the criminal "beyond reasonable doubt" threshold, it still requires credible, admissible evidence.
The most straightforward proof is an admission. If your spouse is willing to sign a sworn affidavit before a commissioner of oaths acknowledging the affair, this constitutes sufficient evidence. Many divorces proceed on adultery grounds through this method when both parties want to avoid the one-year wait and the adulterous spouse cooperates.
Without an admission, acceptable evidence includes:
- Written communications (texts, emails, social media messages) indicating sexual activity
- Photographs or videos showing the affair (must be legally obtained)
- Testimony from the affair partner
- Witness testimony establishing circumstances from which adultery can be inferred
- Financial records showing purchases related to the affair
- Private investigator reports
Evidence must be legally obtained under Ontario law. Secretly recording conversations where you are not a participant, hacking into email accounts, or using illegal surveillance methods may result in evidence being excluded and potential criminal liability. The Ontario Family Law Rules require evidence to be both relevant and lawfully obtained.
The third party need not be named in court documents. You can refer to them as "a person known to the Applicant" if you prefer not to identify them. However, naming the third party and having them provide testimony strengthens your case.
The Condonation Rule: Forgiveness Bars Adultery Claims
Condonation under Divorce Act, s. 11(1)(c) can bar you from using adultery as grounds for divorce. If you discover your spouse's affair and continue living together as a married couple for more than 90 days with knowledge of the infidelity, you have "condoned" the adultery and cannot rely on it for divorce purposes.
The 90-day rule under Divorce Act, s. 11(3) provides a grace period for attempted reconciliation. Spouses may resume cohabitation for up to 90 days total without triggering condonation. This recognizes that couples may try to save their marriage after discovering infidelity. If reconciliation fails within 90 days, the innocent spouse can still proceed with divorce on adultery grounds.
Key elements of condonation:
- Knowledge: You must have actual knowledge of the adultery, not mere suspicion
- Cohabitation: You must continue living together as spouses
- Forgiveness: The cohabitation must indicate an intention to forgive
- Duration: The period must exceed 90 days after discovery
If condonation applies, you can still divorce based on one-year separation. The condonation bar only prevents using that specific instance of adultery as grounds—it does not prevent divorce entirely.
Timeline: Adultery Divorce vs. Separation Divorce in Ontario
The theoretical advantage of adultery divorce is speed, but practical realities often eliminate this benefit. An uncontested divorce based on one-year separation typically takes 4-6 months once the separation period is complete. A contested divorce alleging adultery can take 12-24 months if the other spouse disputes the claim.
| Stage | Separation-Based | Adultery-Based (Admitted) | Adultery-Based (Contested) |
|---|---|---|---|
| Separation Period | 12 months | 0 months | 0 months |
| Application Filing | 1 day | 1 day | 1 day |
| Response Period | 30 days | 30 days | 30 days |
| Evidence/Discovery | Minimal | 1-3 months | 6-12 months |
| Trial (if needed) | Rare | N/A | 6-12 months |
| Judgment | 2-4 months | 2-4 months | 1-3 months post-trial |
| Total Timeline | 16-20 months | 3-8 months | 18-36 months |
If your spouse admits the adultery, you can potentially complete the divorce in 3-8 months, saving roughly 8-12 months compared to waiting for separation. However, if your spouse contests the adultery allegation, the case becomes a trial matter requiring discovery, witnesses, and potentially expert evidence. These contested cases often take longer than simply waiting for one year of separation.
Cost Comparison: Adultery vs. Separation Divorce
Court filing fees are identical regardless of grounds: $669 total in Ontario as of March 2026 ($224 for the Application for Divorce plus $445 for the set-down fee). The significant cost difference lies in legal fees and evidence gathering.
| Cost Category | Separation-Based | Adultery (Admitted) | Adultery (Contested) |
|---|---|---|---|
| Court Filing Fees | $669 | $669 | $669 |
| Legal Fees (Self-Rep) | $0 | $0-$500 | Not advisable |
| Legal Fees (Lawyer) | $1,500-$3,000 | $2,500-$5,000 | $15,000-$50,000+ |
| Private Investigator | N/A | $0 if admitted | $2,000-$10,000 |
| Expert Witnesses | N/A | N/A | $3,000-$10,000 |
| Total Range | $669-$3,669 | $669-$5,669 | $20,669-$70,000+ |
Fee waivers are available for individuals receiving Ontario Works, ODSP, or meeting low-income thresholds. The $669 provincial filing fee can be waived entirely, though the $10 federal fee payable to the Central Registry of Divorce Proceedings cannot be waived.
How to File for Divorce Based on Adultery in Ontario
Filing for divorce on adultery grounds follows the same procedural steps as any divorce, with additional evidentiary requirements:
-
Confirm residency: Either you or your spouse must have lived in Ontario for at least one year immediately before filing
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Gather evidence: Collect all documentation supporting the adultery claim, or obtain your spouse's sworn affidavit admitting the affair
-
Complete Form 8A: Fill out the Application for Divorce, checking the box indicating adultery as grounds
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Prepare supporting affidavit: Draft a sworn statement detailing the facts supporting your adultery claim
-
File at Superior Court: Submit your application at the Superior Court of Justice in your jurisdiction with the $224 filing fee
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Serve your spouse: Arrange service of the application on your spouse through a third party
-
Wait for response: Your spouse has 30 days to respond (60 days if served outside Canada)
-
File divorce record: Once the response period expires, submit your divorce record with the $445 set-down fee
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Obtain judgment: A judge reviews your materials and grants the divorce order
If your spouse contests the adultery allegation, the case will proceed to a case conference and potentially trial. You will need to present evidence and may face cross-examination about your claims.
FAQs: Adultery and Divorce in Ontario
Can I get more money in the divorce if my spouse cheated?
No, adultery does not entitle you to a larger share of property or increased spousal support in Ontario. The Family Law Act and Divorce Act both operate on no-fault principles. Your spouse's infidelity is irrelevant to property equalization and support calculations. The only exception is if your spouse spent significant marital funds on the affair, in which case the court may adjust equalization to account for the financial loss—not the cheating itself.
Do I need to prove adultery with photos or videos?
No, photographic or video evidence is not required to prove adultery in Ontario. The most common proof is a sworn affidavit from the cheating spouse admitting the affair. Courts also accept text messages, emails, witness testimony, and circumstantial evidence establishing adultery on a balance of probabilities. Private investigator reports can help, but are not necessary if other evidence exists.
Will my spouse lose parenting time because they had an affair?
No, adultery has no impact on parenting arrangements in Ontario. Courts determine decision-making responsibility and parenting time based solely on the best interests of the child under Divorce Act, s. 16. A parent's infidelity does not indicate poor parenting ability. The only relevant consideration would be if the affair partner posed a safety risk to children.
What if I forgave the affair but now want a divorce?
If you continued living together as spouses for more than 90 days after discovering the affair, you have condoned the adultery and cannot use it as grounds for divorce. However, you can still divorce based on one-year separation. The condonation rule only bars reliance on that specific affair—it does not prevent divorce entirely. If subsequent affairs occur, each is a separate ground.
How long do I have to file for divorce after discovering adultery?
There is no time limit for filing divorce based on adultery in Ontario. You can file immediately upon discovery or years later. However, the condonation rule applies: if you continue cohabitating for more than 90 days after learning of the affair, you lose the ability to use adultery as grounds. You must separate within 90 days to preserve this option.
Can my spouse use their own adultery to divorce me?
No, under the Divorce Act, s. 8(2)(b)(i), only the innocent spouse can rely on adultery as grounds for divorce. The spouse who committed adultery cannot file for divorce based on their own infidelity. They must either wait for one-year separation, rely on your cruelty (if applicable), or have you file based on their adultery.
Does it matter if the affair was with someone of the same sex?
No, same-sex adultery is legally equivalent to opposite-sex adultery in Ontario. Following the Civil Marriage Act of 2005 and the legalization of same-sex marriage across Canada, sexual intercourse with any third party—regardless of gender—constitutes adultery. The legal consequences (or lack thereof) are identical.
What happens to the affair partner in an adultery divorce?
The affair partner faces no legal consequences in Ontario adultery divorces. Canada eliminated claims for "criminal conversation" and "alienation of affection" decades ago. The third party cannot be sued for damages, cannot be ordered to pay costs, and is not a party to the divorce. They may be named in court documents and called as a witness, but have no legal liability.
Can I spy on my spouse to prove adultery?
No, illegally obtained evidence may be excluded from court and could expose you to criminal liability. Ontario courts follow strict rules about evidence collection. You cannot hack into your spouse's email, secretly record conversations where you are not a participant, or engage in illegal surveillance. Work with a licensed private investigator and family law lawyer to ensure evidence is gathered legally.
Is an emotional affair considered adultery in Ontario?
No, emotional affairs do not legally constitute adultery in Ontario. Under the Divorce Act, adultery requires actual physical sexual intercourse. Online relationships, sexting, emotional intimacy, or romantic attachments that do not involve sexual intercourse are not grounds for adultery-based divorce. You would need to proceed on separation grounds instead.