While you can keep multiple credit cards on file as payment methods in your Twilio project, one card is designated as the “primary” card. Short code payments are always charged to whichever card is designated the primary card.

If you’d like your short code payments on a different card from the one you use for your day to day Twilio costs, you must manually designate that card to be the primary card before your short code renewal is charged. You will receive automated reminders that your short code is about to be renewed via email, which will let you know when to change your primary card.

You can add or change payment methods by logging into your Twilio project here. For more instructions on how to change a payment method or set a primary payment method, please see this FAQ.