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General information only, not medical or audiological advice. Whether a person should use a captioned telephone is a question for that person and a hearing-care professional.
Short answer
A captioned telephone looks and works like an ordinary phone but also shows the other person’s words as text on a screen, a moment after they are spoken. In the United States, federal rules for Internet Protocol captioned telephone service (IP CTS) say that only registered users with hearing loss may use the equipment with the captions on, and they set specific requirements for the device label, the caption control and the volume control.
“Captioncall” is a product name. This page is brand-neutral and describes the category and the rules that apply to it.
Definition and scope
A captioned telephone is a telephone paired with a captioning service. The user hears the caller, as on any phone, and reads captions on the handset’s display or in an app. Hamilton Relay describes its service as meant for people with some hearing loss who struggle on phone calls. This page covers IP CTS as regulated in 47 CFR 64.604, and the CapTel product line from Hamilton Relay as one documented example of how a provider describes its service.
How captions are produced
Hamilton Relay states that its CapTel service uses speech recognition to generate captions and that a live Communication Assistant helps ensure the captions are accurate. It says captions appear “just moments after the other party has spoken.” The service is offered in English or Spanish. Because captions follow speech by a short interval and rely on recognition, a reader should expect the text to trail the voice slightly; the provider’s own wording is “just moments,” not instantaneous.
Hamilton states “The captioning service is free” to the user. Under 47 CFR 64.604(c)(11)(v), the notice required in IP CTS marketing says there is a cost for each minute of captions generated, paid from a federally administered fund.
Line and connection requirements by model
The same provider page lists what each CapTel model needs. This matters for a facility that must confirm a person’s existing phone line before anyone orders a device.
| CapTel model | What the provider says it needs |
|---|---|
| 840PLUS | Telephone service |
| 840i | Internet and phone service |
| 880i | Internet and phone service |
| 2400i | Internet and phone service; an internet-only option is also listed |
| Hamilton CapTel (service) | Telephone service plus high-speed internet, Wi-Fi capable |
Source: Hamilton Relay, CapTel captioned telephone page, https://hamiltonrelay.com/how-it-works/captel-captioned-telephone/, checked 2026-10-30. Model lists change; the provider page is the authority for the current set.
Who may use captions on: the federal rules
47 CFR 64.604 is the Federal Communications Commission’s rule on telecommunications relay service standards. Paragraphs (c)(10) and (c)(11) cover IP CTS. The table summarizes what they say, in the order a procurement or intake reader is likely to need it.
| Topic | What the rule text says (47 CFR 64.604(c)(10)-(11)) |
|---|---|
| Who may use captions on | “No person shall use IP CTS equipment or software with the captioning on” unless the person is a registered user, or an existing user as of March 7, 2013 who meets the stated conditions. |
| Device label | Newly distributed equipment must carry, on its face in a conspicuous place, the label: “FEDERAL LAW PROHIBITS ANYONE BUT REGISTERED USERS WITH HEARING LOSS FROM USING THIS DEVICE WITH THE CAPTIONS ON.” |
| Software notice | Software must show the same notice on the device screen immediately after log-in, each time the consumer logs in. |
| Marketing | Informational materials and websites need a notice that federal law prohibits anyone but registered users with hearing loss from using IP captioned telephones “WITH THE CAPTIONS TURNED ON.” |
| Turning captions on | The captioning control must require only one step to turn on captioning. |
| Volume | Volume must be adjustable separately and independently of the caption feature. |
| Provider records | Providers keep records of the amount paid for the equipment and whether the label was affixed, for a minimum of five years after the consumer ceases to obtain service from the provider. |
Source: 47 CFR 64.604, https://www.ecfr.gov/current/title-47/part-64/section-64.604 (text checked 2026-10-30 at https://www.law.cornell.edu/cfr/text/47/64.604).
Captioned phones and amplified phones
These are different categories. A captioned phone adds text; an amplified phone is about sound level. The rule text above ties the two together in one place: an IP CTS device’s volume must be adjustable independently of the captions, so a captioned phone still has its own volume control. Beyond that category difference, this page makes no claim about amplified phone specifications.
Where it matters for labs, clinics and supply decisions
A captioned telephone is consumer telecommunications equipment, not a laboratory instrument or a clinical device in the sense discussed in what is a medical device. Staff who help a person obtain one can use the sourced points above as a checklist:
- Registered-user restriction: captions on are for registered users with hearing loss, so a shared or demonstration unit in a waiting room or office falls under that restriction.
- Label: confirm the required label text is on the equipment.
- Line type: match the model to the person’s existing service (phone-only versus internet and phone) using the provider’s list.
- Records: the five-year record requirement applies to providers, not to the facility.
Facilities that formalize equipment intake can place such checks inside an equipment procurement policy, and a broader view of how purchasing fits together is in the hospital supply chain guide.
Common misunderstandings
“Anyone can use the captions.”
No. The rule text restricts use with the captions on to registered users, with a narrow existing-user exception. The restriction is about the captions being on, which is why the label and marketing notices use that phrase.
“Free means no one pays.”
The provider describes the service as free to the user. The federal marketing notice states that there is a cost for each minute of captions generated, paid from a federally administered fund.
“Captions are perfectly accurate and instant.”
The provider describes captions as appearing moments after speech, with speech recognition plus a Communication Assistant helping ensure accuracy. That is a small delay and an accuracy aid, not a guarantee of instant, error-free text.
FAQ
What is a captioned telephone?
A phone that shows captions of the other person’s speech on a screen, shortly after they speak, for people with some hearing loss who find phone calls difficult (Hamilton Relay, checked 2026-10-30).
Who can use captions on?
Under 47 CFR 64.604(c)(11)(ii), registered users, and certain existing users as of March 7, 2013 under the stated conditions (47 CFR 64.604, checked 2026-10-30).
What does the device label say?
“FEDERAL LAW PROHIBITS ANYONE BUT REGISTERED USERS WITH HEARING LOSS FROM USING THIS DEVICE WITH THE CAPTIONS ON.”
Does a captioned phone need internet?
It depends on the model. The provider lists the 840PLUS as needing telephone service, and the 840i, 880i and 2400i as needing internet and phone service (2400i also lists an internet-only option).
How is a captioned phone different from an amplified phone?
A captioned phone adds text; an amplified phone concerns volume. They are separate categories, and a captioned phone’s volume is adjustable independently of its captions.
Sources
- 47 CFR 64.604, Telecommunications relay services standards, paragraphs (c)(10)-(11). https://www.ecfr.gov/current/title-47/part-64/section-64.604. Checked 2026-10-30; text also checked at https://www.law.cornell.edu/cfr/text/47/64.604.
- Hamilton Relay, CapTel captioned telephone. https://hamiltonrelay.com/how-it-works/captel-captioned-telephone/. Checked 2026-10-30. CapTel is a trademark of Ultratec, Inc.
