Have you picked up a promotion code from one of our partners? Great! Here's how you use it:
Promotion codes will be redeemed for the credited amount after you've completed the call. Even if you've applied a promotion code, we still ask for credit card information when making a call request, in case that the call goes over the credited amount from the promotion code.
Go to your Account > Settings > Promotions > Apply the given promotional code in the field box.
Your promotion code has been applied when you see it listed under the "apply" button: