Notary Public vs Commissioner of Oaths in Ontario: Which Do You Need?
A notary public in Ontario is an official who can verify signatures, certify true copies of documents and administer oaths, with authority that is recognized internationally. A commissioner of oaths, formally a commissioner for taking affidavits, has a narrower job: administering oaths and taking affidavits and statutory declarations, mainly for use inside Canada. Every notary can do everything a commissioner can, but not the reverse. Because I am an Ontario lawyer, I automatically hold both offices, which is convenient for you: bring the document, and the right hat goes on.
What is a notary public?
Under Ontario’s Notaries Act, a notary public can witness and attest signatures, certify copies as true copies of originals, administer oaths and declarations, and perform the notarial acts foreign governments, banks and institutions rely on. Lawyers and paralegals licensed in Ontario are entitled to act as notaries; certain non-lawyers may be appointed with limited powers. The notary’s seal is the feature international recipients look for, and since Canada joined the Hague Apostille Convention in January 2024, a notarization is also the usual first step before Official Documents Services issues an apostille.
What is a commissioner of oaths?
A commissioner for taking affidavits, created by Ontario’s Commissioners for Taking Affidavits Act, is authorized to administer oaths and affirmations and to take affidavits and statutory declarations. Lawyers and paralegals hold the office automatically; many court clerks, municipal staff and other appointees hold it for specific purposes. A commissioner’s stamp is exactly what Ontario courts and Canadian government forms mean when they say “sworn before a commissioner.” What a commissioner cannot do is notarize a signature on its own, certify true copies, or produce documents for international authentication.
Quick comparison:
| Feature | Notary Public | Commissioner of Oaths |
|---|---|---|
| Primary Role | Authenticates documents, certifies true copies, witnesses signatures, and administers oaths. | Administers oaths, affirmations, affidavits, and statutory declarations. |
| Can Administer Oaths? | ✔ Yes | ✔ Yes |
| Can Witness Affidavits? | ✔ Yes | ✔ Yes |
| Can Certify True Copies? | ✔ Yes | ✖ No |
| Can Verify Signatures for International Use? | ✔ Yes | ✖ No |
| International Document Acceptance | ✔ Accepted by foreign governments, embassies, and international organizations. | ✖ Generally limited to documents intended for use within Ontario or Canada. |
| Common Documents |
• Certified True Copies • Consent to Travel Letters • Passport Copies • Immigration Documents • Powers of Attorney • International Business Documents |
• Affidavits • Statutory Declarations • OSAP Forms • Name Change Forms • Court Documents |
| Official Seal Required | ✔ Yes | ✔ Yes |
| Best Choice When... | You need certified copies, notarized signatures, or documents for use outside Canada. | You only need someone to witness your oath or affidavit for use in Ontario. |
So which one does my document need?
Read what the receiving office wrote. “Sworn before a commissioner for taking affidavits”: a commissioner suffices, and any Ontario lawyer qualifies. “Notarized,” “notarial seal,” “certified true copy,” or any document leaving Canada: you need a notary public. When the instructions are silent or contradictory, the safe move is the notary, since notarial authority includes commissioning; a document can never be under-qualified by having the fuller seal.
Why does one person being both matter?
Because misdiagnosis is the most common wasted trip in this field. People book a commissioner appointment somewhere, then discover the foreign bank wanted a notarial certificate; or they pay notary prices for a domestic form a commissioner covers. When the same licensed lawyer holds both offices, the diagnosis happens in the room and the correct act happens immediately, at the price of the act you actually needed.
Three real-world diagnoses
A bank in England asks for a “notarially certified” passport copy: notary, because the certification and seal must satisfy a foreign compliance team, and a commissioner’s stamp would bounce. An Ontario court form ends with “sworn before me at”: commissioner is legally sufficient, and since every lawyer is one, the fee should reflect the simpler act. A power of attorney for property in the Philippines, with consular instructions attached: notary, followed by the consulate’s own authentication chain, executed exactly per their checklist. The pattern: domestic sworn forms travel on a commissioner’s stamp; anything crossing a border wants the notarial seal, and often more after it.
FAQ's
Frequently Asked Questions
Is a lawyer automatically a notary public in Ontario?
Yes. Every person licensed by the Law Society of Ontario as a lawyer is entitled to exercise the powers of a notary public, and is a commissioner for taking affidavits by virtue of office.
Can a commissioner stamp a document going to another country?
The stamp can be applied, but foreign recipients usually reject it because they require notarial certification, often followed by an apostille. Documents leaving Canada should start with a notary.
Are notary fees regulated in Ontario?
No statute fixes private notarial fees, which is why prices in the GTA range so widely. That is also why this site posts every fee in advance.
Does a pharmacist, bank or MPP office count?
Some MPP and municipal offices offer limited free commissioning for certain domestic forms, and it is a fine option when your document qualifies and the wait suits you. They cannot notarize, certify copies or handle international paperwork.
Is a notary in Quebec the same as a notary in Ontario?
No. Quebec notaries are a distinct legal profession who draft deeds and practise law within Quebec’s civil law system. An Ontario notary public is the common law officer this guide describes. Documents moving between the provinces sometimes need requirements read carefully for exactly this reason.