The default Phone number and Mobile phone number fields only accept numbers and the following characters that are commonly found in phone numbers: + - ( ) . x. You can further validate phone numbers in form submissions by restricting the length of the number a visitor is able to enter.
- In your HubSpot account, navigate to Marketing > Files and Templates > Files.
- Click the name of a form.
- Hover over the Phone number field and click the pencil icon edit.
- In the left pane, in put a Minimum and Maximum number length. If a visitor inputs a phone number that does not meet these length restrictions, they will be prevented from submitting the form.
- In the upper right, click Publish.
Please note: phone number length restrictions must be set on an individual form basis.