Notary Public vs Commissioner of Oaths in Ontario
Both can take your oath. Only one can certify copies and notarize documents for use abroad. Here is how to tell which one you need.
In Ontario, a commissioner of oaths can administer oaths and witness affidavits and statutory declarations. A notary public can do all of that, and can also certify true copies, notarize signatures and prepare documents for use outside Canada. If you’re unsure, a notary covers both.
Side-by-side comparison
| Task | Commissioner of oaths | Notary public |
|---|---|---|
| Commission an affidavit | Yes | Yes |
| Statutory declaration | Yes | Yes |
| Certified true copy of an original | Generally no | Yes |
| Notarize a signature (e.g. power of attorney, invitation letter) | No | Yes |
| Documents for an apostille or use abroad | Generally no | Yes |
When a commissioner of oaths is enough
If all you need is to swear or affirm that the contents of a document are true, and the document will be used in Ontario or Canada, a commissioner can handle it. Common examples are affidavits for small claims court and statutory declarations for government forms.
When you need a notary public
- The receiving organization asks for a notarized document or a notary seal
- You need certified true copies of passports, degrees or transcripts
- The document is going outside Canada and may need an apostille
- You’re signing a power of attorney, invitation letter or travel consent letter that should be notarized
Our office is a notary public and commissioner of oaths, so either type of document can be completed in one visit. See affidavits & declarations and certified true copies.
Frequently asked questions
Can a commissioner of oaths certify a true copy?
Generally no. Certifying a document as a true copy is a notarial act, so it’s done by a notary public, not by a commissioner of oaths.
Can a notary public commission an affidavit?
Yes. A notary public in Ontario can also administer oaths and commission affidavits and statutory declarations, so you don’t need to see a separate commissioner.
Who can be a commissioner of oaths in Ontario?
Lawyers and licensed paralegals are commissioners by virtue of their licence, and the province appoints other people, such as some municipal staff and employees of certain organizations, as commissioners. Some town halls offer commissioning to residents.
Which one do I need for a document going overseas?
Usually a notary public. Documents for use outside Canada typically need a notary’s signature and seal so that Ontario can then add an apostille or authentication.
Is it cheaper to use a commissioner?
Sometimes, but if your document also needs a certified copy, a notary signature or use abroad, a commissioner can’t complete it and you’d need a second appointment.
Related: Affidavit vs statutory declaration · What a notary costs
Need a document notarized?
Same-day appointments in Scarborough, 7 days a week. $20 for the first signature and seal.