Phone verification with one-time passcodes (OTP)

Growform sends a one-time passcode by SMS and asks the lead to enter it before the form is submitted. You know the number is real and that the lead is holding the phone.

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What is OTP phone verification?

OTP phone verification confirms that a lead controls the phone number they entered. A one-time passcode is sent to the number by SMS, and the lead types it back into the form. Only someone holding the phone can read the passcode, so a correct code shows that the number exists, receives messages and belongs to the lead. A form that works this way is sometimes called an OTP verification form.

What is the difference between phone validation and phone number verification?

Validation checks that a number appears to be valid, and phone number verification proves that the lead has the phone. Phone number validation with Twilio Lookup runs in the background and catches mistyped or made-up numbers. It cannot tell you whose number it is. A passcode can, in exchange for one extra action from the lead.

The two checks suit different forms. Validation adds no friction, so it fits almost any lead form. Verification asks more of the lead, so it fits offers where an unreachable lead is expensive.

When should you verify phone numbers with a passcode?

Verify when a bad number costs you more than losing a few leads at the passcode step. Three situations usually meet that test.

You sell leads, and buyers return the ones they cannot reach.
Your sales team calls every lead, as with mortgage, insurance or solar appointments.
Your offer attracts false details, such as a free quote.

Lead verification works best late in a multi-step form, after the lead has answered your qualifying questions and has a reason to finish. On the same step, email validation can check the address and a consent checkbox can record permission to call.

How phone verification works in your form

The lead enters a number

Your form asks for a phone number on the contact step, as it does today.

A passcode arrives by SMS

A one-time passcode is sent to that number through Twilio.

The lead types the code

The form continues once the code matches, and a lead who gave a number they do not own never receives it.

What a verified phone number is worth to your business

Your contact rate rises.
Each number has received a text message and been confirmed by the lead who owns it.
Buyers have less reason to return a lead.
A number confirmed by passcode cannot be disconnected, mistyped or invented.
False submissions stop at the passcode.
Someone who enters another person's number never sees the code and cannot complete the step.
Your lead count reflects reachable leads.
The form is submitted only after the code has been entered correctly.