What changes the moment we separate?

There is no formal step called "separating"

Ontario law does not require you to file anything, register anything or tell a court that you have separated. You are separated once you are living separate and apart with at least one of you intending not to resume the relationship — the Divorce Act says spouses are treated as separated for any period either of them had that intention, even under the same roof.

That flexibility cuts both ways. A short reconciliation attempt of up to ninety days in total does not restart the clock if it does not work out, but there is also no certificate to point to later. Write down the date and how you told each other; it becomes evidence if the date itself is ever disputed.

The valuation date starts running

For married spouses, separation with no reasonable prospect of resuming cohabitation fixes the valuation date under the Family Law Act — the date property and debts are valued for equalization. Everything owned and owed on that date matters; what happens to your finances afterward mostly does not change the calculation.

This is why the date you separate is worth pinning down early, even informally. Bank balances, investment values and debts all move day to day, and a dispute about the date can become a dispute about the numbers.

The matrimonial home does not change hands

Both spouses have an equal right to possession of a matrimonial home under section 19 of the Family Law Act, regardless of whose name is on title, and neither of you can sell or mortgage it without the other's consent, a court order, or a release in a separation agreement. Moving out does not give up that right and does not, by itself, change who owns the home.

Deciding who stays, at least for now, is usually the first practical question. It can be worked out between you, or if you cannot agree, a court can order exclusive possession on an interim basis.

Parenting and support continue under the same rules

Parents have equal entitlement to decision-making responsibility for their children under the Children's Law Reform Act until an agreement or order changes it, and whatever schedule the children are actually living under tends to become the reference point for later discussions. Support obligations do not pause either; a parent's duty to contribute to a child's needs exists independently of any agreement.

None of this requires a lawyer or a court on day one. It does mean that what you do informally in the first weeks — who has the children when, who pays what — often shapes what comes next.

If divorce is the goal, the one-year clock starts now

The most common ground for divorce in Ontario is that the spouses have lived separate and apart for at least one year, under section 8 of the Divorce Act. You do not have to wait a year to start a court case — an application for parenting, support or property can be filed right away, and the divorce itself can be added once the year has passed.

The other grounds, adultery and cruelty, exist but are rarely used; they require proving fault in court, while the one-year route needs only the passage of time.