Set up and use RTT calling in FaceTime on Mac
If you have difficulties hearing or speaking, or want to call someone who does, you can use Real-Time Text (RTT) for your phone calls, if your carrier supports it. When someone calls you, a notification appears on your Mac and you can take the call as an RTT call.
RTT calls you make and receive on your Mac use cellular minutes—cellular charges may apply. Your Mac, iPhone, or iPad must meet these requirements.
Set up RTT phone calls
On your iPhone, go to Settings > Accessibility.
Tap RTT/TTY. (Depending on your carrier, you might see RTT or TTY instead.)
Turn on Software RTT/TTY.
When RTT is on, the RTT button appears in the status bar. You can choose additional options for RTT calls on your iPhone.
On your Mac, choose Apple menu > System Settings, click Accessibility in the sidebar, then click RTT on the right. (You may need to scroll down.)
Turn on RTT.
Note: If you don’t see RTT, check that you completed all the steps to set it up. If you still don’t see RTT, it may not be supported on your Mac.
Choose additional options.
For more information, click in the bottom-right corner.
When RTT is set up on your Mac, the RTT button appears—for example, in a card in the Contacts app or in FaceTime—to indicate that you can make or receive an RTT call.
Make RTT calls from FaceTime on your Mac
To make RTT calls, you need to sign in to FaceTime, set up your iPhone and Mac for phone calls, and turn on RTT phone calls.
Important: When making an emergency call in the U.S. on your Mac, special characters or tones are sent to alert the operator. The operator’s ability to receive or respond to these tones can vary depending on your location. Apple doesn’t guarantee that the operator will be able to receive or respond to an RTT call.
Go to the FaceTime app on your Mac.
Click New FaceTime.
Enter a phone number in the dialog, then press Return.
Tip: If the person is saved in your contacts list with a phone number, you can just enter the person’s name, or select them from Suggested.
Click next to , then choose RTT Call or RTT Relay Call.
Choose RTT Relay Call when you need to call someone who may not have RTT capabilities—this option connects the call to a person who can assist you. See Change RTT settings for accessibility for more information about the RTT relay number.
Note: If you’re restricted to calls with only certain people, appears next to those people you can’t call.
After the other person accepts the call, click RTT, then start typing.
If you selected Send Immediately in RTT settings for Accessibility, the recipient sees each character as you type. Otherwise, press Return to send the message.
Answer RTT calls on your Mac
On your Mac, when a notification appears in the top-right corner of the screen, do one of the following:
Accept an RTT call: Click , then click . (RTT is available even if you haven’t set it up.)
Decline a call: Click .
Tip: If the call came from someone you don’t want to receive calls from, you can block the caller.
Decline a call and send a message using iMessage: Click next to , choose Reply with Message, type your message, then click Send. Both you and the caller must be signed in to iMessage.
Decline a call and set a reminder to call back later: Click next to , then choose how long you want to wait to receive a reminder. When the time comes, you receive a notification—click it to view the reminder, then click the link in the reminder to start the call.
You can’t receive a call from someone who’s restricted by communication limits in Screen Time, but the call appears as a missed call in the FaceTime window or in Notification Center.