Legal requirements for transactional messages

Transactional messages are those that you can send to customers to keep them up-to-date on a transaction they have made with you, such as a purchase, appointment, or other booking.

You can use the Subscribers API to programmatically opt-in customers who want to receive transactional messages. The Telephone Consumer Protection Act (TCPA) mandates that each person must provide consent to receive transactional messages.

It is recommended you collect a customer’s consent by using a checkbox when you collect the phone number during checkout. You will need to design and implement a transactional opt-in unit yourself, and this opt-in unit can be pre-checked. The following image is an example transactional opt-in checkbox within the checkout flow:

You must send a screenshot of the transactional opt-in unit to your Client Strategy Manager or the White Glove team ( for review prior to implementation. Our team will review the opt-in unit with compliance in mind.

After the opt-in unit is reviewed, we will provide you with the unique SignUpSourceID that is needed in your API call.

The customer will be opted in to transactional messages if:

  1. The customer entered their phone number.
  2. The transactional opt-in unit was checked at the time of purchase.