Knowledge-Based Authentication
Knowledge-Based Authentication (KBA) is a secure identity verification process requiring users to answer at least four out of five personalized questions within two minutes, generated from their personal and credit history using their legal name, U.S. address, birthdate, and last four digits of their Social Security number or ITIN, with up to three attempts allowed within 48 hours and specific wait times between retries to ensure safe digital notarization.
Knowledge-Based Authentication (KBA) is a secure, identity-verification quiz designed to protect your information and ensure a safe environment for your digital notarization. This article will guide you through the KBA process, covering everything from time limits to what happens if you need to retry. During the quiz, you will have two minutes to correctly answer at least four out of five questions based on your personal history. Completing this step confirms your identity and allows you to move forward seamlessly into your live notary session.
What You'll Need
To generate your KBA questions, you'll need to provide:
- Your full legal name
- Your current or former U.S. address
- Your date of birth
- The last 4 digits of your U.S. Social Security number or Individual Taxpayer Identification Number (ITIN)*
We use this information to pull questions from your credit history and other public records. You'll generally need at least 6 months of credit history to generate the required questions.
Proof only uses the last 4 digits of your Social Security number to generate your KBA questions — nothing else.
How It Works
Proof uses secure third-party data sources to generate your questions. Here's what to expect:
- Questions will vary for each person.
- They may cover your property, vehicles, phone numbers, and other personal history.
- Some questions may be about others with a shared property interest.
You have 2 minutes to answer 4 out of 5 questions correctly to pass.
If You Don't Pass
Don't worry if you don't pass on the first try — you can retake the quiz immediately. After that, wait times apply. Here's a summary:
- First attempt: You can retake immediately.
- Second attempt (first retake): 24 hours from the first attempt.
- Third attempt (second retake): 48 hours from the first attempt.
You cannot attempt KBA more than 3 times in 48 hours. Any attempt after the lockout period restarts the timer. Proof Support cannot unlock your quiz — this restriction is required to protect your identity. If you had a scheduled signing, contact the person who sent you the transaction to let them know.
Troubleshooting
My information isn't being recognized
- Double-check your name, date of birth, address, and Social Security number for errors.
- Enter your birth date in MM-DD-YYYY format. For example, July 12, 1989 should be entered as 07-12-1989.
- Make sure you're using your full legal name. If you recently changed your name, try your former name.
- If you've recently moved or are traveling, try using your former U.S. address.
No questions were generated
In some cases, a valid Social Security number may still not generate enough questions. This can happen if:
- There isn't enough personal data on record to generate the minimum number of questions.
- All available KBA questions have already been used.
Summary Checklist
- Have your full legal name, address, date of birth, and last 4 digits of your SSN or ITIN ready.
- Answer 4 out of 5 questions correctly within 2 minutes to pass.
- If you fail, you can retry immediately. After two failed attempts, wait times of 24 and 48 hours apply.
- If locked out, contact whoever sent you the transaction to let them know.
Still unsure? If you're still having trouble after trying the troubleshooting tips above, contact the person or organization that sent you the transaction to arrange an alternative form of notarization. For technical help, contact Proof Support.
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