Choosing a Ground for Your Ontario Divorce: A Practical Guide

Every Ontario divorce application has to check one specific legal box: a ground. The Divorce Act gives you exactly three to choose from, and most people default to the one they've heard of without thinking through whether it actually fits their situation. Picking the right ground for your Ontario divorce affects how straightforward the process is, so it's worth a few minutes of thought before you file.

This guide walks through all three grounds, why one dominates in practice, and how to think about which one applies to you.

The Three Grounds, at a Glance

Only one ground needs to be established — you don't need to prove more than one, and most applicants only ever plead separation.

Why Most Ontario Divorces Rely on Separation

The separation ground doesn't require either spouse to prove the other did anything wrong. You simply need to show you've been living separate and apart for the period the Divorce Act sets out — as of mid-2026, that's generally one year, though statutory periods can be adjusted, so confirm the current requirement before you rely on it for your filing.

Because no fault has to be proven, separation is typically the calmer, less document-heavy path, and it's compatible with a joint application where both spouses apply together.

You don't need a formal separation agreement in place to use this ground — you need to actually be living separate and apart, which can, in some circumstances, happen even under the same roof, though that's a fact-specific question worth discussing with a lawyer.

When Adultery or Cruelty Might Actually Make Sense

The adultery and cruelty grounds exist for situations where a spouse doesn't want to, or can't, wait out a separation period. Neither ground carries the same waiting requirement that separation does.

That said, both come with real costs:

• You'll need to put forward evidence to support the claim
• The process tends to be more adversarial, since you're alleging specific misconduct
• It can end up slower and more expensive overall than a straightforward, uncontested separation-based application, despite skipping the waiting period

For most people, the trade-off doesn't make sense unless there's a specific reason a separation-based application isn't workable.

What the Court Still Needs, No Matter Which Ground You Pick

Choosing a ground doesn't end the analysis. Before granting any divorce, a court needs to be satisfied that reasonable arrangements have been made for the support of any children of the marriage. This requirement applies across all three grounds — it isn't something separation, adultery, or cruelty applications get to skip.

How to Decide: A Short Checklist

• [ ] Have you and your spouse actually been living separate and apart, or could you be soon?
• [ ] Is there a reason you can't wait out the separation period (urgency, safety, or another factor)?
• [ ] If considering adultery or cruelty, do you have evidence you could realistically put before a court?
• [ ] Have you and your spouse worked out, or started working out, arrangements for any children?
• [ ] Would a joint application be realistic given how you and your spouse are currently communicating?

Walking through these questions with a lawyer before you file can save real time later, since switching grounds mid-application adds complexity you'd rather avoid.

Frequently asked questions