Commissioner of oaths or notary public: which do you need in Ontario?
By Misbah Shajjan, Licensed Paralegal. Updated November 1, 2026.
In Ontario, a commissioner of oaths witnesses affidavits and statutory declarations. A notary public can do the same and can also certify true copies and notarize signatures, which documents used outside Ontario often require. Bring the unsigned document and government photo ID.
When a commissioner of oaths is enough
- Affidavits for court and tribunals
- Statutory declarations (lost documents, common-law union, residency)
- OSAP and many government forms
When you need a notary public
- Certified true copies of degrees, transcripts and IDs
- Signatures on documents for use outside Canada
- Travel consent letters (recommended)
- Documents that will be apostilled
Apostilles
Since January 11, 2024, Canada is part of the Apostille Convention. Ontario documents for use in member countries can be apostilled by the province after they are notarized where needed.
What to bring
- The document, unsigned
- Valid government photo ID
- Originals of anything to be certified as a true copy
Questions
How much does a notary cost in North York?
At our office, every document is $25 plus HST.
Can you notarize documents online?
Certified true copies must be made from originals in person. Call us to confirm what can be done for your document.
Need help with this? See our Notary Public and Commissioner of Oaths service.
This guide is general information, not legal advice about your situation.