Why can't I cancel my services immediately?

Billing for the Services commences when AT&T has provisioned the Services. Recurring charges for each month's Services will be billed one month in advance. Billing is based on a 30-day cycle. Non-recurring and usage-based charges for the Services generally will be billed in the billing cycle following the transaction. Your first bill for Services may include pro-rated charges for a partial monthly period prior to the beginning of your first monthly billing cycle. Upon termination, subject to applicable law, your effective date of cancellation will be the last day of your current billing cycle and you will receive Service until the end of your billing cycle (exceptions may apply to certain promotional periods and must be in writing). You will not receive a prorated credit or refund for any remaining days of Service in your billing cycle after termination. Your Service will continue until the end of the bill cycle. A downgrade fee may apply if you make changes to your Service within thirty (30) days of Service provisioning or later programming orders.