There are are two fees you'll have to pay monthly for use of the mobile messaging tool. The first fee is a partnership with Action Network to access the mobile messaging features, which is based on how many messages you send per month, similar to a partnership for email features.
Twilio also charges for the services that you use. Pricing is based on the destination and type of message you are sending. They follow a pay-as-you-go pricing model to ensure a fair price no matter what you build. This pricing should be used as a guide. It does not include everything you might be charged for, depending on the features you use, and includes discounts Action Network has negotiated on your behalf.
You can learn more about number types and Twilio fees in the US here, and Canada here.
This pricing does not apply to users outside of the US and Canada, to check pricing in your country check here. For a full pricing chart, click here.
Both of these fees will show up on your bill that you pay to Action Network.