Which court hears a Sarnia family matter — and whether it is one court or two — is the first thing we confirm. We handle separation, divorce and parenting matters online across Ontario, at published flat fees — you do not need to come to an office.
Sarnia sits in Lambton County, and family matters for Sarnia residents are heard in the city itself — the Sarnia Courthouse.
Ontario runs family matters through two different arrangements, and which one applies depends on where you live. In some areas the Family Court — a branch of the Superior Court of Justice — hears the entire file: divorce, property, parenting, support and child protection together. Elsewhere the work is split, with the Ontario Court of Justice hearing parenting, support, protection and adoption while divorce and property division go to the Superior Court. Which arrangement covers Sarnia decides whether your matter sits in one court or two, and it is the first thing we confirm when we open a file — before anything is filed anywhere.
Sarnia is a lower-tier municipality within Lambton County, and court jurisdiction in Ontario follows those boundaries rather than city limits — which is why the answer above is about Lambton County, not about Sarnia on its own.
You are not alone in this. Residents of Brooke-Alvinston, Dawn-Euphemia, Enniskillen, Lambton Shores, Oil Springs, Petrolia, Plympton-Wyoming, Point Edward and St. Clair and one other municipality are heard at the same court, because all of them sit inside Lambton County. There are 11 municipalities in the county in total.
The Sarnia Courthouse handles family matters, Superior Court civil filings, Small Claims Court, enforcement of orders, a Crown Attorney's office and the Victim/Witness Assistance Program. It is in the city itself, so there is no travel out of town for a filing or an appearance.
One court or two is not cosmetic: it changes which forms are filed and where, how parenting and property issues travel together, and how quickly the whole matter moves. We confirm it before anything is filed.
The Ontario child support table applied to the income you enter, and the Advisory Guidelines range for spousal support. Both are estimates — the notes under each result say what they leave out, and they leave out a lot. There is more detail on the child support calculator and spousal support calculator pages.
Where a court orders supervised parenting time or a supervised exchange, it happens at a designated centre funded by the Ministry of the Attorney General — not at the courthouse. Serving Sarnia:
Sources: supervised access centres. Retrieved 2026-08-10.
Most separations in Sarnia never see the inside of the Sarnia Courthouse. They are settled by a written separation agreement — parenting, support and property dealt with by negotiation, sometimes with a mediator. Court is what you use when agreement is not possible, or when you need an order only a judge can make.
That matters for cost. A negotiated agreement is a fixed, knowable piece of work. A contested court file is not, because its length depends on the other side. We quote the first as a fixed scope and are honest with you about when a matter has moved beyond it.
A married spouse's claim to equalization of property is time-limited, and the one-year separation ground for divorce must be complete when the divorce is decided — not when the application is filed, so you can start before the year is up. Neither depends on where in Lambton you live, but both are easier to miss when nobody has told you they exist.
If children are involved, the language changed: Ontario and the federal Divorce Act now speak of decision-making responsibility and parenting time rather than custody and access. Older agreements and older advice still use the old words, which causes confusion in Sarnia as everywhere else.
Divorce and property division are heard by the Superior Court of Justice. The Ontario Court of Justice handles parenting, support, child protection and adoption but cannot grant a divorce. For Sarnia, family matters are dealt with through the Sarnia Courthouse.
No. Most separations in Ontario are settled by a written separation agreement negotiated between the parties, often with mediation. Court is for matters that cannot be agreed, or where an order is needed.
It varies with court volume. The one-year separation ground under the Divorce Act must be complete when the divorce is decided, not when the application is filed — so a spouse can start before the year is up.
Generally no for a separation agreement. Each spouse should have independent legal advice, and an agreement is much harder to challenge later when both parties had it.
Yes. We are an Ontario firm and work online across the province, so you do not need to be near an office to open a file.
Open your Sarnia file online in minutes — a licensed Ontario lawyer reviews it before a dollar is owed.