The difference between a witness and a notary comes down to authority: a witness is a private person who watches you sign a document and signs to confirm they saw it, while a notary public is a state-commissioned official who verifies your identity, can place you under oath, and attaches a formal certificate and seal. Some documents need one, some need the other, and a few important ones — like a will with a self-proving affidavit — need both.
What a Witness Does
A witness physically watches you sign a document and then signs it too. That’s the whole job. They don’t check your ID. They don’t administer an oath. They’re there so that if anyone later disputes whether you actually signed, a real person can say they were in the room and watched it happen.
Witnesses are most commonly required for wills, trusts, advance directives, powers of attorney, and certain real estate documents. The specific rules vary by state, but the general expectation is that a witness be a legal adult with the mental capacity to understand what they’re observing. Most states also require witnesses to be disinterested, meaning they don’t benefit from the document’s contents. For wills in particular, a beneficiary who serves as a witness can trigger challenges during probate or even forfeit their inheritance in some states.
What a Notary Public Does
A notary public is appointed by a state government to serve as an impartial verifier with extra powers. Before watching you sign, a notary checks your identity, typically through a government-issued photo ID or personal knowledge of you. The notary then completes an official certificate, signs it, and applies their official seal to the document.1American Society of Notaries. Your Basic Duties as a Notary Public
Notaries can also administer oaths and affirmations, which means they can put you under penalty of perjury before you sign a sworn statement. That’s the main thing that separates notarization from simple witnessing: a notary adds a layer of state-backed verification that courts and institutions treat as more authoritative.
Documents that commonly require notarization include real estate deeds and mortgage documents, powers of attorney, affidavits, loan agreements, and certain business filings. Many states require notaries to keep a journal recording each notarial act, including the date, the document type, and how the signer’s identity was verified. Over 20 states currently mandate this journal requirement, though specific rules vary.
To become a notary, a person applies through their state government, meets eligibility requirements (typically being at least 18, a legal resident, and able to read and write English), and in many states completes a training course. Commissions usually last four years and must be renewed.
Acknowledgments vs Jurats
Not all notarizations work the same way. The two most common types are acknowledgments and jurats, and the difference affects whether you’re allowed to sign the document before your appointment.
With an acknowledgment, you confirm to the notary that you signed voluntarily and understand the contents. You can sign the document before you meet the notary. You just need to appear in person and acknowledge that the signature is yours. Real estate deeds and contracts commonly use acknowledgments.
With a jurat, you swear under oath that the contents are true, and you must sign in the notary’s physical presence. You cannot pre-sign a document that requires a jurat. Affidavits and sworn statements typically require jurats.2American Society of Notaries. Presence Requirement
This distinction trips people up. Someone shows up to a notary appointment having already signed an affidavit, and the notary has to refuse the notarization because a jurat requires the signature to happen right there. Check the certificate language on your document before your appointment. If it says “subscribed and sworn to before me,” that’s a jurat, and you need to wait to sign.
Side-by-Side Differences
The practical differences come down to authority, what gets verified, and the paper trail left behind.
- Authority. A notary is a state-commissioned public official. A witness is a private individual with no government appointment.
- Identity verification. A notary checks your ID or relies on personal knowledge of you. A witness typically just needs to know you or be told who you are.
- Documentation. A notary completes a formal certificate, applies an official seal, and in many states records the act in a journal. A witness signs the document and may add their printed name and address.
- Oath power. A notary can place you under oath, making false statements a criminal offense. A witness has no such authority.
- Cost. Witnesses typically serve for free. Notary fees are set by state law and generally range from $2 to $25 per signature for a standard acknowledgment, though some states allow higher fees for specialized services like remote online notarization.
When a Document Needs Both
Some documents require both witnesses and notarization. The most common example is a self-proving affidavit attached to a will. This is a short notarized form where you and your witnesses swear under oath that the will was properly signed. During probate, the court can accept the will without needing to track down your witnesses and bring them in to testify. Because probate often happens years after a will is signed, when witnesses may have moved or died, a self-proving affidavit can save an estate real trouble.
To execute one, you, your witnesses, and a notary all need to be in the same room. The notary puts everyone under oath, you and the witnesses sign the affidavit, and the notary completes and seals it. Everyone should bring valid photo ID.
Can One Person Serve as Both
Usually not. Most professional notary organizations recommend against it, and several states explicitly prohibit a notary from acting as both a witness and the notary on the same document. The notary’s role is to be an independent verifier, and that independence gets muddied if they’re also a participant in the signing. In states that allow it under narrow circumstances, a notary still cannot notarize their own signature, which creates a practical barrier since witness signatures on self-proving affidavits often need notarization themselves. The safer approach is to use separate people for each role.
Remote Online Notarization
Remote online notarization lets you get a document notarized over a video call instead of appearing in person. As of 2025, approximately 47 states have enacted laws authorizing some form of remote online notarization. The process uses audio-video technology, digital signatures, and multi-factor identity verification, typically knowledge-based authentication questions drawn from your credit history or public records, plus credential analysis of your photo ID.
Remote notarization doesn’t change the fundamental requirements. The notary still verifies your identity, watches you sign, administers oaths when needed, and applies a digital seal and certificate. Fees for remote notarizations are often higher than in-person fees, typically $25 per signature, since states frequently set separate fee caps for remote services. Witnessing requirements are a separate matter from notarization, and state rules on remote witnessing of documents like wills vary considerably.
How to Prepare for the Signing
A little preparation prevents wasted trips.
For notarized documents, bring a current, government-issued photo ID such as a driver’s license, passport, or state ID card. The notary needs to match your face and name to the document.1American Society of Notaries. Your Basic Duties as a Notary Public Check whether your document requires an acknowledgment or a jurat. If it’s a jurat, do not sign before your appointment. If it’s an acknowledgment, pre-signing is fine in most states, but signing in front of the notary avoids any ambiguity. Make sure the document is complete with no blank spaces that could be filled in later. Notaries are trained to refuse incomplete documents.
For witnessed documents, line up your witnesses before the signing date. Choose people who are legal adults, mentally competent, and have no financial interest in the document. For a will, that means your witnesses should not be beneficiaries or their spouses. Do not sign until your witnesses are present and watching. A witness who signs but didn’t actually see you sign hasn’t fulfilled their role, and that gap can be used to challenge the document later.
What Happens When Something Goes Wrong
Errors in witnessing or notarization can unravel entire transactions and legal arrangements.
With faulty witnessing, the most common casualty is a will. During probate, an interested party can challenge a will by presenting evidence that execution didn’t follow state law, such as evidence that a witness was underage, didn’t actually watch the signer sign, or was a beneficiary in a state that prohibits that. If the challenge succeeds, a court can declare the will invalid, and the estate gets distributed under the state’s default intestacy rules, which is often not what the person who wrote the will intended.
With faulty notarization, a notarization performed without proper identity verification, without the signer’s physical presence (when required), or without a completed certificate can result in the document being declared invalid by a court or rejected by the receiving party. If a notary skips the oath on a jurat, the entire notarization fails. For the person relying on the notarized document, an invalid notarization on a real estate deed or loan agreement can stall a closing, trigger title insurance disputes, or require the entire signing process to be repeated.