Postpaid mobile phone

The postpaid mobile phone is a mobile phone for which service is provided by a prior arrangement with a mobile network operator. The user in this situation is billed after the fact according to their use of mobile services at the end of each month. Typically, the customer's contract specifies a limit or "allowance" of minutes, text messages etc., and the customer will be billed at a flat rate for any usage equal to or less than that allowance. Any usage above that limit incurs extra charges. Theoretically, a user in this situation has no limit on use of mobile services and, as a consequence, unlimited credit. This service is better for people with a secured income.

Postpaid service mobile phone typically requires two essential components in order to make the 'post-usage' model viable:

The bill itself is an important component of the services which acts as an ambassador of the service provider and at times as an evidence of the service itself. The bill needs to be readable, comprehensible as well as aesthetically attractive for the subscriber to be interested enough to see details other than the bill amount.

The United States is an example of a country dominated by postpaid providers including Verizon, AT&T, Sprint, and T-Mobile, although a smaller market has been captured by prepaid providers such as Boost Mobile, Virgin Mobile, MetroPCS, Cricket Wireless and TracFone, many of which use postpaid providers networks (e.g. MetroPCS is carried on the T-Mobile network).

The alternative billing method is a prepaid mobile phone where a user pays in advance for credit which is then consumed by use of the mobile phone service.

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