Who This Is For / When to Use
This feature is intended for teams that:
Collect phone numbers through forms or surveys
Require verified, reachable phone data
Want to reduce spam or fake submissions
Need higher trust in SMS-based follow-ups
What SMS Verification Does
When SMS Verification is enabled on a form or survey:
Respondents must verify their phone number before submission
A one-time verification code (OTP) is sent via SMS
Each submission records whether the phone number was verified
Verification is submission-specific, not contact-based.
Why SMS Verification Is Important
SMS Verification helps by:
Improving data integrity through phone ownership validation
Preventing fraud and automated submissions
Ensuring deliverability for future SMS communication
How to Enable SMS Verification (Builder Setup)
Step 1: Open the Form or Survey Builder
Go to Sites in the left navigation
Open Forms or Surveys
Click Add Form or edit an existing form
Step 2: Add or Select a Phone Field
Ensure the form includes a Phone field.
Select the phone field to open its settings panel.
Step 3: Enable Phone Validation
In the phone field settings, enable Validate Phone
Save the form
This activates SMS verification for that form or survey.
How SMS Verification Works for Respondents
Step 4: Respondent Enters Phone Number
When filling out the form, the respondent enters their phone number.
Step 5: Verify Phone and Complete Verification
The Verify Phone button appears after a valid number is entered
The respondent receives an SMS with a verification code
After entering the correct code, the phone number is confirmed
A success message confirms verification before submission.
How Verified Numbers Appear in Submissions
Each submission includes a Phone Verified field:
Yes — phone number successfully verified
No — verification not completed or failed
This field can be used for filtering, workflows, or reporting.
Key Feature Details
Verification is required every time the form is submitted
Existing contacts must re-verify if the toggle is enabled
Verification confirms current phone ownership, not historical data
OTP SMS messages are billable
Common Issues and Fixes
Verification Code Not Received
Confirm the phone number format is correct
Ask the respondent to request a new code
Verify SMS balance and delivery status
Phone Not Marked as Verified
The verification code was not entered
The entered code was incorrect
The user exited the form before completion
Existing Contact Asked to Verify Again
This is expected behavior. Verification confirms that the current respondent owns the phone number.
FAQ
How does SMS verification work?
The respondent enters a phone number, clicks Verify Phone, receives an SMS code, and enters that code to confirm ownership before submitting the form or survey.
What happens if the verification code is incorrect or not entered?
The phone number will not be marked as verified. The respondent can request a new code.
How can I tell if a phone number was verified?
Each submission includes a Phone Verified field showing Yes or No.
Are OTP messages billed?
Yes. Each verification SMS is billed as an outbound OTP message.
Can SMS verification be enabled or disabled per form?
Yes. SMS verification is configured individually for each form or survey.
Do existing contacts need to verify again?
Yes. If verification is enabled, the respondent must verify during that submission to confirm current phone ownership.