The short answer
A commissioner of oaths is generally authorized to administer oaths and take affidavits or statutory declarations. A notary public can perform those functions and can also provide notarial acts such as witnessing signatures and certifying true copies, depending on the document and the receiving organization.
The safest answer is always found in the instructions from the court, government office, bank, school, employer, or foreign authority requesting your document. The words they use determine which appointment is accepted.
When you may need a commissioner of oaths
- An affidavit or statutory declaration must be sworn or affirmed.
- A government form names a commissioner, notary, or other authorized official.
- A provincial application requires a declaration made in Ontario.
During commissioning, the authorized official confirms your identity, administers the oath or affirmation, watches you sign, and completes the jurat or declaration wording. The official is not giving legal advice about the statement itself.
When a notary public is the better choice
- A receiving organization requests notarization specifically.
- You need a certified true copy of an original document.
- A signature must be notarized for use outside Ontario or Canada.
- You need several document types handled during one appointment.
Notarization can involve identity verification, signature witnessing, document comparison, and completion of a notarial certificate. International recipients may also require authentication, apostille, or legalization after notarization.
Questions to ask before you book
- Does the recipient require a commissioner of oaths, a notary public, or either?
- Must the document be signed in front of the official?
- Are original documents, witnesses, translations, or special wording required?
- Will the recipient accept a remote online notarization?
Bring the full instructions with you. If the wording is unclear, contact the organization that issued the form before the appointment.
Related services
For sworn statements, see affidavit and statutory declaration notarization. For document copies, see certified true copies. You can request an appointment and include the exact requirement in your message.
Common questions
Is a commissioner of oaths the same as a notary?
No. A commissioner generally takes affidavits and declarations, while a notary can handle those acts and additional notarial services.
Do I need a notary or commissioner for an affidavit?
Usually either an authorized commissioner or notary can take an affidavit, but the receiving organization controls what it accepts.
Can a notary certify a true copy?
A notary may certify a true copy by comparing it with the original, subject to the document and recipient's requirements.