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Internet Protocol (IP) Captioned Telephone Service

Telecommunications Relay Service allows persons with who are deaf, hard of hearing, deaf-blind or who have speech disabilities to place and receive telephone calls. There are several forms of TRS that consumers can use, depending on the nature of the disability and whether they have some hearing and/or ability speak. This guide explains the Internet Protocol Captioned Telephone Service, but for detailed descriptions of the other forms of TRS, see the FCC's TRS consumer education article in the Consumer Help Center.

How IP Captioned Telephone Service works

Users of IP CTS place a call over a CTS telephone (which is equipped with special software and a screen for displaying captions). The call is automatically connected to both the receiving party (over a traditional phone line) and a communications assistant.  The communications assistant hears and repeats or "re-voices" everything the receiving party says, and voice recognition technology automatically transcribes the communications assistant's words from voice into text. The text is transmitted directly to the IP CTS user.  The use of voice recognition technology allows the captions to appear on the IP CTS user's telephone, nearly simultaneously with the other party's spoken words.  There are also versions of IP CTS that are used with a smartphone or personal computer. 

Benefits of IP CTS

IP CTS offers people with hearing loss a more effective way to use the telephone and communicate in their homes or workplaces.  In addition, with some forms of the service, captions can be displayed on a screen in large text, using variable fonts and colors, which helps accommodate individuals with hearing disabilities who also have low vision.

TRS Fund support

The FCC has ruled that IP CTS calls are an approved form of TRS that may be compensated from the Interstate TRS Fund.  Like all TRS calls, the relay costs associated with IP CTS are not paid directly by users of the service.

Temporary requirements

To ensure that IP CTS is provided efficiently to people who need to use this service, the Commission recently established the following requirements:

  • IP CTS providers are prohibited from offering financial and other rewards to consumers, charitable organizations, audiologists or other professionals for the referral and registration of new IP CTS customers. 
  • New IP CTS users must self-certify to the provider that (1) they have a hearing loss requiring use of the service to effectively communicate over the phone, (2) they understand that the captioning service is provided by a live communications assistant, and (3) they understand that the cost of the IP CTS calls is funded by the TRS Fund.  If the user obtains IP CTS equipment for free or for less than $75, a third-party professional must provide certification that the user needs IP CTS to communicate effectively over the phone.  However, individuals who spend $75 or more for their end user equipment need only provide self-certification (1 and 2).
  • IP CTS phones must have a default setting that allows the captions to be turned off, so that consumers need to turn on the captions for each call.

Emergency call handling procedures

The FCC has adopted procedures for IP CTS that require the provider, at minimum, to automatically and immediately transfer an emergency call to the appropriate 911 call center or ensure that appropriate personnel are notified of the emergency.

IP CTS providers must also: 1) prioritize emergency calls over nonemergency calls; 2) communicate to the emergency personnel answering the call the name of the TRS user, the location of the emergency, the name of the provider, the communications assistant's call-back number and identification number; and 3) re-establish contact between the caller and emergency personnel if the call is disconnected.

Filing a complaint

If you have a problem with IP CTS, first try to resolve it with the provider. If you are unable to resolve it directly, you can file a complaint with the FCC. You have multiple options for filing a complaint:

  • File a complaint online
  • By phone: 1-888-CALL-FCC (1-888-225-5322); TTY: 1-888-TELL-FCC (1-888-835-5322); ASL Videophone: 1-844-432-2275
  • By mail (please include your name, address, contact information and as much detail about your complaint as possible):

Federal Communications Commission
Consumer and Governmental Affairs Bureau
Consumer Inquiries and Complaints Division
445 12th Street, S.W.
Washington, DC 20554

What to include in your complaint

If filing a complaint by mail, please also indicate:

  • Whether you are filing a complaint on behalf of another party, and if so, the party's name, address, email address, day time phone number and your relationship to the party.
  • Preferred format or method of response (letter, fax, voice phone call, email, TRS, TTY, ASCII text, audio recording or Braille).
  • That your complaint is about TRS.
  • The name, address and telephone number (if known) of the company or companies involved with your complaint.
  • A brief description of your complaint and the resolution you are seeking, and a full description of the equipment or service you are complaining about, including date of purchase, use or attempt to use.

For more information

For more information about FCC programs to promote access to telecommunications services for people with disabilities, visit the FCC's Disability Rights Office website.

Accessible formats

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Internet Protocol (IP) Captioned Telephone Service Guide (pdf)

Updated: October 13, 2015

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