To cancel your service with Vivint, you need to submit a Notice of Cancellation in writing 30 days before you decide to cancel. Early termination fees may apply. This notice can be sent via email, fax or by mail. In the notice, you must include the following: the date of your notice, service number, a note entailing why you wish to cancel and your signature. For additional information on Vivint’s cancellation policy, please visit the provider’s website.