As you use Twilio services (minutes, SMS messages, phone numbers, transcriptions, etc.), we draw down your account balance. We’ll notify you by email when your balance hits $5.00, and then again when your balance reaches $0. When your balance reaches $0, your account will be suspended. If a call is in progress at this time, it can complete naturally, and result in a negative balance. You will be unable to place or receive any calls, SMS messages, etc. until your accounts is recharged.
On your billing page, you can manually recharge, or have us automatically recharge your balance when it falls below a chosen threshold.
If you have Auto Recharge on, your account will be billed if it goes below $10 by default. You can change this default to up to $1000.00 in your account's Auto Recharge preferences.