How Does Adultery Affect Support and Divorce in Ontario?

Adultery as a Ground for Divorce

Under the Divorce Act, adultery is one of three grounds for establishing marriage breakdown. Unlike the one-year separation ground, adultery can be cited immediately — there is no waiting period. However, the spouse alleging adultery must prove it, which can be difficult and contentious. Most people choose to rely on the one-year separation period even when adultery has occurred.

Does Adultery Affect Property Division?

In Ontario, adultery generally has no effect on property division. The equalization of net family property is a purely mathematical exercise based on assets and debts. Marital misconduct — including adultery — is not a factor in the equalization calculation. A court will not reduce an equalization payment simply because one spouse was unfaithful.

Does Adultery Affect Spousal Support?

Adultery has very limited relevance to spousal support in Ontario. Unlike some other jurisdictions, Ontario family law does not generally reduce spousal support because of a recipient spouse’s infidelity. Support is based on economic need, the length of the marriage, and the roles the spouses took on during the marriage — not moral conduct.

Exception: New Relationship of the Recipient Spouse

If the spouse receiving support enters into a new common law relationship, this may affect their entitlement to ongoing support. This is not because adultery is penalized but because remarriage or cohabitation is a material change in circumstances that can reduce or eliminate financial need.

Does Adultery Affect Parenting Arrangements?

Adultery alone generally does not affect parenting time or decision-making responsibility. Courts focus on each parent’s ability to meet the children’s needs and the best interests of the child — not on the moral behaviour of the parents in relation to each other. Only where the conduct directly affects the children’s well-being would it be considered.

Practical Considerations

While adultery may not carry significant legal weight, it can significantly affect the emotional dynamics of a separation, making it harder to reach negotiated settlements. Where adultery has occurred, it is often more productive to focus on reaching a fair legal resolution than on establishing fault, which tends to increase costs and conflict without improving legal outcomes.