A notary’s personal knowledge of a signer is a legally recognized way to identify someone for a notarial act based on your own past dealings with them, not on a driver’s license or passport. Under the Revised Uniform Law on Notarial Acts (RULONA), which a majority of states follow, you meet the standard when the signer “is personally known to the officer through dealings sufficient to provide reasonable certainty that the individual has the identity claimed.” The method is real, but it rests entirely on your judgment and your reputation, and at least one large state does not allow it at all. Before you use it, you need to know what “reasonable certainty” actually requires, when to decline, and how to document what you did.
What Reasonable Certainty Really Requires
Personal knowledge is not recognition. Spotting a familiar face, remembering someone from a single meeting, or knowing a person only by a nickname does not clear the bar. The standard asks for an acquaintance built through repeated, meaningful interaction over time, strong enough that you could state under oath that the individual in front of you is the exact person named in the document.
Most states that define the term track RULONA closely. Florida, for example, defines “personally knows” as “having an acquaintance, derived from association with the individual, which establishes the individual’s identity with at least a reasonable certainty.” The common phrase is “reasonable certainty,” and the practical test is whether you’d be comfortable defending the identification in court. If the thought gives you pause, you do not have personal knowledge.
No statute sets a minimum number of meetings or months of acquaintance. The standard is qualitative, and that’s deliberate. It forces you to exercise genuine judgment rather than count encounters. Someone you’ve worked with daily for two years almost certainly qualifies. A neighbor you last saw five years ago and vaguely remember probably does not.
How to Decide Whether Your Knowledge Is Enough
Experienced notaries run through a mental checklist before relying on personal knowledge. None of this is codified, but it reflects how a court or licensing board would examine the identification if it were ever challenged.
- How often have you spoken with this person face to face?
- How long have you known them?
- Have you seen people you trust interact with this person and call them by the same name?
- Do you have any lingering uncertainty about who they are?
- Would you defend this identification in court if the document turned out to be fraudulent?
If any of these questions gives you hesitation, ask for a government-issued ID instead. You always have the right to request documentary identification, even when personal knowledge could technically apply. Nothing in the law obligates you to use personal knowledge just because you happen to know the signer, and asking a friend for an ID is a professional safeguard, not an insult.
Workplace Relationships
Office, bank, and law firm notaries get these requests constantly from coworkers. Whether a work relationship qualifies depends on depth, not proximity. Sharing a building with someone you’ve nodded at for six months is not the same as working on a team with them daily. A useful test: can you describe the person’s role, their routine, and their full legal name without looking anything up? Meeting someone earlier that same day never qualifies, no matter how thorough the introduction.
When Appearance Has Changed
People age, lose weight, grow beards, change hairstyles. If you haven’t seen the signer in a long time and something about their appearance creates even a flicker of doubt, personal knowledge is no longer safe. The standard asks for reasonable certainty right now, at the moment of notarization, not reasonable certainty five years ago. Trust the instinct and ask for ID.
When You Shouldn’t Use Personal Knowledge Even If You Could
The situations where personal knowledge feels most natural are often the same situations where conflict-of-interest rules disqualify you from notarizing at all. A notary cannot act on a transaction in which they have a direct financial or beneficial interest, and that rule applies regardless of how the signer is identified. If your name appears on the document as a party, beneficiary, or agent, you cannot notarize it, even if you know the signer perfectly well.
Family members are a related trap. Several states explicitly prohibit notarizing documents for a spouse, parent, or child. Others extend the restriction to siblings, domestic partners, and step-relatives. Even where no specific statute applies, professional ethics standards strongly recommend declining any notarization for a blood relative or relative by marriage. The concern isn’t that you’ll misidentify your spouse; it’s that your impartiality as a witness is compromised, and documents notarized by someone with a personal stake invite later challenges.
The practical point: knowing someone well enough to meet the personal knowledge standard does not mean you should be the notary for their transaction. If you benefit from the document, are named in it, or are closely related to the signer, find another notary.
State Variation and One Important Boundary
Most states permit personal knowledge, but not all. At least one large state prohibits notaries from relying on personal knowledge entirely, requiring satisfactory documentary evidence for every notarization no matter how well the notary knows the signer. In that state, even a neighbor of twenty years must produce an acceptable ID, and the prohibition covers all notarial acts, including acknowledgments and jurats.
Other states permit personal knowledge but impose conditions, such as requiring you to record in your journal exactly how you know the signer, or limiting the method to certain notarial acts. Using a prohibited identification method can void the notarization, so confirm your state’s current rule before relying on personal knowledge. Your secretary of state or commissioning authority publishes this information, and it’s worth checking even if you were taught otherwise during initial training. Rules change.
Personal knowledge is also one of three identification methods under RULONA. The other two are a current government-issued ID (driver’s license, passport, state ID, and in some states a military ID) and a credible identifying witness who personally knows the signer and swears to their identity before the notary. If you don’t personally know the signer and they lack valid ID, a credible witness is the bridge; the witness rules themselves vary by state.
Documenting a Personal Knowledge Identification
When you use personal knowledge, your documentation needs to be explicit enough that someone reviewing the record years later can tell exactly what happened. Two records have to match: the notarial journal and the certificate attached to the document.
The Journal Entry
In states that require a journal, the identification field should state clearly that the signer was identified through personal knowledge rather than by a document. Record the signer’s full legal name as it appears on the document, along with the date, time, type of notarial act, and a description of what was signed. Complete the entry before finishing the notarization. If you wait until afterward, the signer may leave and you’ll be stuck with a gap you cannot fix.
Not every state mandates a journal, but keeping one even where it’s optional is one of the smartest habits a notary can develop. If a signer’s identity is later disputed, the journal is your primary evidence that you followed proper procedure. Without it, you’re left defending a notarization from memory, possibly years after the fact.
The Notarial Certificate
The acknowledgment or jurat certificate attached to the document should reflect the same identification method recorded in your journal. Many certificate forms include language indicating how the signer was identified; make sure the wording matches your state’s current requirements. Some states have updated their certificate language to remove references to personal knowledge, which is another cue to verify whether your state still permits the method.
Consistency matters because recording offices and courts flag discrepancies. A journal entry saying “identified by driver’s license” paired with a certificate claiming personal knowledge is exactly the kind of mismatch that gets documents rejected or subpoenaed.
Personal Knowledge in Remote Online Notarization
Remote online notarization, where the signer appears by live video, is now authorized in most states, and personal knowledge remains a valid identification method for remote sessions in nearly all of them. When you use personal knowledge during a remote session, the signer typically does not have to complete the multi-part identity verification that would otherwise apply: credential analysis of an ID shown on camera, combined with knowledge-based authentication questions drawn from their credit and personal records.
The same standard still governs. Genuine, established familiarity sufficient for reasonable certainty does not get weaker over video, but it doesn’t get stronger either. In practice, personal knowledge comes up less often in remote work because online platforms are built to identify strangers, but when you already know the signer well, it can streamline the session considerably.
What Happens If You Get It Wrong
Misidentifying a signer under the personal knowledge standard carries heavier professional risk than a bad ID check, because your judgment is the only thing backing the identification. There is no forged document to point to and no technology failure to blame. If the person turns out to be an imposter, the question becomes whether you were reckless or dishonest in claiming personal knowledge.
Consequences vary by state. They can include revocation or suspension of your commission, civil liability for damages caused by the fraudulent document, and fines. In some states, performing a notarial act knowing the identification is false is a criminal offense. Even an honest mistake can result in the notarization being voided, which may unwind real estate transactions, invalidate powers of attorney, or create title defects that take years to clear.
Errors and omissions policies written for notaries generally cover mistakes made during notarizations, including failures to catch an imposter, but coverage specifics depend on the policy language. Insurance will not prevent commission revocation or criminal prosecution; it can cover defense costs and civil damages.
The simplest protection is to use personal knowledge conservatively. When genuine doubt exists, ask for ID. No legitimate signer will object, and the few seconds it takes to check a driver’s license can prevent consequences that last far longer.