What makes a separation agreement binding in Ontario: in writing, signed by both of you and witnessed (Family Law Act s. 55). Who can witness, why legal advice matters, filing it with the court, and what a notary does.
Last updated: October 12, 2026
Separation Agreement Ontario: How to Sign and Witness It
Quick answer: In Ontario a separation agreement is a domestic contract under the Family Law Act. To be enforceable it must be made in writing, signed by both of you and witnessed (s. 55(1)). The Act does not require a notary, does not set a number of witnesses, and does not require you to sign at the same time. What protects the agreement later is full financial disclosure and each of you understanding what you sign, which is why each spouse usually gets separate legal advice (s. 56(4)). A notary can be your neutral witness: Minute Notary witnesses separation agreements in person on a mobile visit, and commissions the sworn paperwork around them online, such as the Form 26B affidavit for filing the agreement with the court. A notary does not draft the agreement or give legal advice.
Most of the work in a separation agreement is the negotiation: who keeps the home, how support is paid, how parenting time is shared. The signing is the short part, but it is the part the law is strict about. An agreement that was never properly signed and witnessed cannot be enforced, however fair its terms.
This guide covers what a separation agreement can include, the three formal requirements, what makes a court set one aside, how the signing works with a notary, filing the agreement with the court, and how it relates to a divorce. If you are still drafting, our free separation agreement template lays out the usual sections. If you have a question about your own document, contact us or call (613) 434-5555.
Key Takeaways
| Question | Answer | Where it comes from |
|---|---|---|
| When is it binding? | Only when made in writing, signed by both parties and witnessed | Family Law Act s. 55(1) |
| Does it need a notary? | No. Any witness satisfies the Act; a notary is a neutral witness who checks ID | s. 55(1) names no witness |
| Can a court set it aside? | Yes: undisclosed significant assets or debts, a party who did not understand it, and more | s. 56(4) |
| What about the children's terms? | A court can set them aside for the child's best interests or the child support guidelines | s. 56(1) and (1.1) |
| Do we have to file it with a court? | No. Filing lets the support terms be enforced like a court order | s. 35(1) and (2), Form 26B |
| Online or in person? | Witnessing: in person, on a mobile visit. The Form 26B affidavit: online | O. Reg. 431/20 |
What a Separation Agreement Can Cover
Section 54 of the Family Law Act lets two people who lived together and are now living separate and apart make an agreement on their rights and obligations. It covers both married spouses and common-law partners: the test is that you cohabited, not that you married. The agreement can deal with:
- Property: who owns what, and how it is divided.
- Support: spousal support and child support.
- Children: decision-making responsibility, parenting time, and their education and moral training.
- Anything else needed to settle your affairs, such as debts, the family home, or a vehicle.
A separation agreement is one of the domestic contracts in Part IV of the Act, alongside marriage contracts (s. 52) and cohabitation agreements (s. 53); our guide to cohabitation agreements and marriage contracts covers those two. The signing rule below applies to all of them, and to any later agreement that changes or cancels one.
The Three Formal Requirements: Writing, Signatures, a Witness
Section 55(1) is short: a domestic contract is unenforceable unless it is "made in writing, signed by the parties and witnessed." Each part matters.
- In writing. A spoken deal, however clear, is not a separation agreement. The same rule applies when you later amend or cancel the agreement: the change also has to be in writing, signed and witnessed.
- Signed by the parties. Both of you sign. Many lawyers also have each party initial every page, so no page can be swapped later.
- Witnessed. Someone watches each signature being made, then signs as the witness.
What the section does not say is just as useful:
- It does not say who the witness must be. Choose an adult who is not a party and has nothing to gain from the agreement; a relative of one spouse invites an argument later.
- It does not set a number of witnesses. Follow the witness lines in your agreement. If your lawyer drafted it for a particular signing arrangement, use that. The notary can be the witness.
- It does not require you to sign together. Each of you can sign at a separate appointment, as long as each signature is witnessed.
- It does not require a notary. A notary is simply a witness who checks government photo ID and records who signed, which makes the signing easy to prove if it is ever questioned.
What Makes a Court Set an Agreement Aside
A properly signed agreement can still be challenged. Under section 56(4), a court may set aside a domestic contract, or part of it:
- if a party did not disclose significant assets, or significant debts or other liabilities, that existed when the contract was made;
- if a party did not understand the nature or consequences of the contract; or
- otherwise under the law of contract, for example where someone signed under pressure.
The terms about children get extra scrutiny. A court can disregard a provision about decision-making responsibility or parenting time when that is in the child's best interests (s. 56(1)), and a child support provision that is unreasonable under the child support guidelines (s. 56(1.1)).
That is why the work before the signing matters more than the signing itself:
- Exchange full financial disclosure. Each spouse lists income, assets and debts, with documents. If the matter goes to court, that disclosure becomes a sworn financial statement; see our Form 13.1 guide.
- Get separate legal advice. The Act does not require independent legal advice, but it is the usual answer to "did you understand what you signed?" Each spouse sees their own lawyer, never the same one. Many lawyers then sign a certificate of independent legal advice that is attached to the agreement.
- Take your time. Sign only the final version, once you have both had advice.
What a notary can and cannot do: A notary public checks each signer's government photo ID, watches each signature being made, and signs as the witness. A notary can also commission any affidavit or statutory declaration that goes with the agreement. A notary does not draft the agreement, review it for fairness, advise on support or property, or give independent legal advice. For those, each spouse needs their own family lawyer.
How the Signing Works with Minute Notary
Why it is in person. Ontario lets wills and powers of attorney be witnessed over video under set conditions (Succession Law Reform Act s. 4; Substitute Decisions Act s. 3.1), and lets affidavits and statutory declarations be commissioned remotely (O. Reg. 431/20). The Family Law Act has no such provision for domestic contracts, so we witness separation agreements in person, on a mobile visit: the notary comes to your home, office or another place that suits you. The notary signs as the witness.
- Finish the agreement first. Both of you have had legal advice and agree on the final version. Print it and leave every signature line blank. If you need printing, we can bring it at $0.40 per page (black and white).
- Get in touch. Contact us or call (613) 434-5555. Tell us whether you will sign together or separately, and how many signed originals you need.
- On the visit: each signer shows valid government photo ID, signs (and initials, if your lawyer asked for it) while the notary watches, and the notary signs as the witness.
- After the visit: each of you keeps a signed original. If you sign at separate appointments, the second visit is a second trip.
Filing the Agreement with the Court
You do not have to file a separation agreement with the court. Section 35(1) lets a party file it with the Ontario Court of Justice or the Family Court of the Superior Court of Justice, together with an affidavit stating that the agreement is in effect and has not been set aside or varied. Once filed, its support provisions can be enforced, and varied, as if they were an order of that court (s. 35(2)).
The affidavit is Form 26B, Affidavit for Filing Domestic Contract with Court (PDF). Unlike the agreement, it is a sworn statement, so it can be commissioned online: you swear or affirm it on a short video appointment and sign while the notary watches. See our guide to Form 26B and Form 6B, sworn online. Whether filing is right for you is a question for your lawyer.
Separation Agreement vs Divorce
A separation agreement does not end a marriage. Only a court can grant a divorce. Under the Divorce Act (s. 8(2)), the breakdown of a marriage is usually shown by the spouses having lived separate and apart for at least one year; adultery and cruelty are the other grounds. You do not have to wait that year to sign a separation agreement. Many couples sign soon after they separate, and the agreement's terms often carry into the divorce later.
When you apply for the divorce itself, the affidavit for divorce is Form 36, which can also be sworn online; see our Form 36 guide and the wider divorce documents guide. Common-law partners do not divorce; for them the separation agreement is the main document. Our common-law rules in Ontario guide explains how that relationship is treated.
Other Paperwork Around a Separation
These are sworn documents, so they can be done online by video:
- A statutory declaration that you live separate and apart, when a bank, insurer, pension plan or government office asks you to confirm it under oath. Start from our statutory declaration of living separate and apart template.
- Form 26B, to file the agreement with the court.
- Form 36, the affidavit for divorce.
- Vehicle paperwork, if the agreement moves a car from one spouse to the other. Our car ownership transfer guide covers the ServiceOntario forms.
Common Mistakes to Avoid
- Signing before both of you have had advice. It is the first thing a court looks at under s. 56(4).
- Leaving out an asset or a debt. Non-disclosure of significant assets or debts is a ground to set the agreement aside.
- Signing with no witness. Without one, the agreement is unenforceable under s. 55(1).
- Choosing a witness with a stake in it. A neutral adult is easier to rely on later than a family member of one spouse.
- Changing it informally. An amendment needs writing, both signatures and a witness, just like the original.
- Expecting the notary to check the deal. The notary witnesses signatures; the lawyers advise on the terms.
Pricing
| Service | Fee | Note |
|---|---|---|
| Witnessing a separation agreement (mobile visit) | $24.95 per seal + $60 travel fee (up to 30 km from our nearest office in Ottawa or Toronto), once per trip | Plus HST and card processing |
| Form 26B affidavit for filing with the court (online) | $24.95 per stamp | Plus HST and card processing |
| Statutory declaration of living separate and apart | $24.95 per stamp | Online, plus HST |
Note: the first signer is included; if more than one person signs the same document, each additional signer is charged an additional-signer fee of $24.95. The travel fee covers up to 30 km from our nearest office in Ottawa or Toronto; beyond that, an additional travel fee applies.
All fees are shown in full before you pay. See every posted rate on our pricing page.
Frequently Asked Questions
Does a separation agreement need to be notarized in Ontario?
No. Section 55(1) of the Family Law Act makes a domestic contract, a separation agreement included, unenforceable unless it is made in writing, signed by the parties and witnessed. It does not require a notary. Many people still sign in front of one because a neutral witness who checks photo ID makes the signing easier to prove later, and the same notary can commission any affidavit that goes with the agreement.
Who can witness a separation agreement in Ontario?
The Family Law Act says the agreement must be witnessed, but it does not say who the witness must be or how many witnesses there must be. In practice, choose an adult who is not a party to the agreement and has nothing to gain from it; a notary public is one option. Follow the witness lines in your agreement, and if your lawyer drafted it with a particular signing arrangement, use that. The notary can be the witness.
Can a separation agreement be signed or witnessed online in Ontario?
Ontario's rules for witnessing over video cover wills and powers of attorney, and the Family Law Act has no equivalent, so Minute Notary witnesses separation agreements in person, on a mobile visit. The sworn paperwork around the agreement can be done online, for example the Form 26B affidavit for filing it with the court, or a statutory declaration that you live separate and apart.
Do we both have to sign at the same time?
Section 55(1) does not require it. Each spouse can sign at a separate appointment, as long as each signature is witnessed. Tell us when you book whether you will sign together or separately, so we can plan one visit or two.
Is independent legal advice required for a separation agreement?
The Act does not require it, but a court can set aside a domestic contract if a party did not understand its nature or consequences, or if significant assets, debts or other liabilities were not disclosed (s. 56(4)). Separate legal advice for each spouse, plus full financial disclosure, is the usual way to protect the agreement. A notary cannot give that advice.
Does a separation agreement make us divorced?
No. A separation agreement settles your affairs; only a court can grant a divorce. Under the Divorce Act, living separate and apart for at least one year is the usual way to show the marriage has broken down. Married spouses still apply to the court for the divorce itself.
How much does it cost to have a separation agreement witnessed?
On a mobile visit, the posted rate is $24.95 per seal plus a $60 travel fee once per trip (up to 30 km from our nearest office in Ottawa or Toronto; beyond that, an additional travel fee applies), plus HST and card processing. The first signer is included; each additional signer on the same document is charged an additional-signer fee of $24.95. A Form 26B affidavit for filing the agreement with the court can be sworn online for a flat $24.95 per stamp plus HST.
Final Recommendation
Do the hard part first: full financial disclosure, then separate legal advice for each of you on the final version. Then sign it properly: in writing, both signatures, each one watched by a neutral witness. A notary on a mobile visit gives you that witness with an ID check on record. If you later file the agreement with the court, the Form 26B affidavit can be sworn online in a few minutes.
Book Your Appointment
Need your separation agreement witnessed, or a Form 26B affidavit sworn to file it with the court? Minute Notary witnesses domestic contracts on a mobile visit and commissions the sworn paperwork online.
- Contact us: Ask a question or request a visit
- Call: (613) 434-5555
- Service page: Mobile notary
- Free template: Separation agreement
- Related guide: Form 26B and Form 6B, sworn online
- Hours: Every day, Saturday and Sunday included, 8:00 AM to 8:00 PM (Ottawa time)
Sources
- Family Law Act, R.S.O. 1990, c. F.3 (Ontario), ss. 35, 52–56
- Divorce Act, R.S.C. 1985, c. 3 (2nd Supp.), s. 8
- Ontario Court Forms — Family Law Rules forms (Form 26B: Affidavit for Filing Domestic Contract with Court)
- Succession Law Reform Act (Ontario), s. 4
- Substitute Decisions Act, 1992 (Ontario), s. 3.1
- O. Reg. 431/20: Administering Oath or Declaration Remotely (Ontario)
This article was written using AI.
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About the author
Kai Mai
Co-founder & Chief Technology Officer, Minute Notary
Kai Mai writes and edits the Minute Notary guides, working from the published federal and Ontario guidance each article links, and from what Ottawa clients actually run into with certified copies, affidavits, statutory declarations, travel consent letters, and immigration paperwork. These guides are general information written by our editorial team — not legal advice, and not a professional opinion on your document. The receiving authority always has the final say.