Commissioner of oaths in Ontario
A Commissioner for Taking Affidavits administers oaths, affirmations and declarations for documents used in Ontario. Here is what a commissioner can do, how it differs from a notary public, and how to have your document commissioned.
What can a Commissioner for Taking Affidavits do in Ontario?
Oaths, affirmations and declarations.Commissioners for Taking Affidavits Act
A commissioner administers oaths, affirmations and declarations for documents used in Ontario — for example affidavits and statutory declarations. They do not certify true copies or give legal advice.
- Affidavits
- Statutory declarations
- Online where eligible
- Government photo ID
How commissioning works
You meet an authorized Ontario commissioner, confirm your identity, and swear, affirm or declare that the contents of your document are true. The commissioner then completes and signs the jurat.
Not a notarial act: A commissioner cannot certify true copies or issue notarial certificates — that is a notary public's role.
General legal information for Ontario residents, not formal legal advice.
What a commissioner can do
- Administer an oath or affirmation on an affidavit
- Take a statutory declaration
- Commission letters that are declared to be true
- Mark and endorse exhibits attached to an affidavit
What a commissioner cannot do
- Certify a true copy of an original document (a notary public does this, in person)
- Witness signatures as a notarial act, or issue a notarial certificate
- Give legal advice or confirm that your statements are true
- Guarantee that a court, government or institution will accept the document
Commissioner or notary — which do I need?
If you are swearing or affirming an affidavit or making a statutory declaration for use in Ontario, a commissioner can help. If you need a copy certified as a true copy, a signature witnessed as a notarial act, or a document prepared for use outside Canada, you need a notary public. We confirm which applies to your document before you book.
General information only — not legal advice. Acceptance of a commissioned document is always the receiving institution’s decision.
Commissioner of oaths — common questions
What is a Commissioner for Taking Affidavits?▾
A person authorized under Ontario's Commissioners for Taking Affidavits Act to administer oaths, affirmations and declarations for documents used in Ontario — for example affidavits and statutory declarations.
What is the difference between a commissioner of oaths and a notary public?▾
A commissioner administers oaths, affirmations and declarations. A notary public can do that and also certify true copies, witness signatures and issue notarial certificates, including for documents used outside Ontario. Which one you need depends on what the receiving institution requires.
Can a commissioner commission my document online in Ontario?▾
Oaths, affirmations and statutory declarations can be commissioned by video under O. Reg. 431/20, where the document is eligible. Certified true copies and signature witnessing cannot — those need a notary public and, for copies, an in-person appointment.
Does a commissioner give legal advice?▾
No. Commissioning confirms you swore or declared the contents before an authorized person. It is not legal advice and does not verify that the statements are true. For advice about your situation, speak with a licensed Ontario lawyer.
What do I need to bring?▾
Valid government-issued photo ID and the completed but unsigned document. You swear, affirm or declare in front of the commissioner — do not sign in advance.
More general questions are answered on our FAQ page.