New rules for home Internet providers and wireless carriers require them to be truthful about how much their service actually costs.

As part of the transparency requirements in the Federal Communications Commission's net neutrality order, Internet providers have to clearly detail all charges, such as modem rental and installation fees, and disclose the full monthly price that will go into effect after any promotional pricing expires.

The new disclosure rule is more specific than a previous one, the FCC said.

"The existing transparency rule defines the required disclosure of 'commercial terms' to include pricing, privacy policies, and redress options," the FCC's new order said of the pre-existing rule. "While we do not take additional action concerning the requirement to disclose privacy policies and redress options, the record demonstrates need for specific required disclosures about price and related terms."

The new rule specifies that home Internet providers and cellular carriers must make the following disclosures:

Price—the full monthly service charge. Any promotional rates should be clearly noted as such, specify the duration of the promotional period, and note the full monthly service charge the consumer will incur after the expiration of the promotional period.

Other Fees—all additional one time and/or recurring fees and/or surcharges the consumer may incur either to initiate, maintain, or discontinue service, including the name, definition, and cost of each additional fee. These may include modem rental fees, installation fees, service charges, and early termination fees, among others.

Data Caps and Allowances—any data caps or allowances that are a part of the plan the consumer is purchasing, as well as the consequences of exceeding the cap or allowance (e.g., additional charges, loss of service for the remainder of the billing cycle).

"[T]hese disclosures may have been required in certain circumstances under the existing transparency rule in order to provide information 'sufficient for consumers to make informed choices,'" the FCC said. "Here, we now require that this information always be disclosed."

These requirements for broadband are different from the "truth-in-billing" rules that apply to telephone service.

The transparency rule won't go into effect right away. The net neutrality bans on blocking, throttling, and paid prioritization will take effect 60 days after publication in the Federal Register, but new disclosure requirements require an additional approval by the Office of Management and Budget to comply with the Paperwork Reduction Act.

Deceptive advertising is a real problem for consumers. DirecTV just got sued by the Federal Trade Commission, which accused the TV provider of deceptive advertising that tricked customers into paying hundreds more dollars after discounted pricing expired.

The FCC rules apply to broadband rather than TV service, but could lead to similar actions that force Internet providers to be more honest about what their services actually cost. It might prevent situations like this one, where a customer's $90 Time Warner Cable bill jumped to $190 after two years: