RTT, or real-time text, most often turns on “randomly” because of a combination of default carrier settings, accidental activation through accessibility shortcuts, and occasional software glitches after updates. The feature is baked into modern smartphones as a federally required accessibility tool, which means it can be surprisingly persistent even after you think you’ve turned it off.
What RTT Actually Does
Real-time text is an accessibility feature that transmits text character by character during a phone call, so the other person can read what you’re typing as you type it, without hitting send. The FCC required wireless carriers to support RTT by mid-2021 as a replacement for the older TTY technology used by people who are deaf or hard of hearing. Because of that mandate, every major carrier and phone manufacturer builds RTT into their devices. It’s not an app you installed. It lives deep in your phone and calling settings, and carriers sometimes enable it by default.
Carrier Defaults and OS Updates
The most common reason RTT seems to turn itself on is that a software update or carrier settings update resets the feature to its default state. When your phone installs an iOS or Android update, accessibility preferences can revert, and since carriers are required to support RTT, the default is often “on” or “visible.” You might not notice until your next phone call, when a text input box suddenly appears on your call screen.
On some Samsung Galaxy phones, users have reported there isn’t even a true off toggle. The only options are “always show” and “visible during calls,” meaning the RTT button stays present in some form no matter what. This makes it feel like the feature keeps coming back because, on certain devices, it was never fully gone.
Accidental Activation on iPhone
On iPhones, RTT lives under Settings, then Accessibility, then RTT/TTY. A toggle called “Software RTT” controls whether the feature is active. But there’s a second way it can activate: the Accessibility Shortcut. If RTT or TTY is assigned to your Accessibility Shortcut, triple-clicking the side button (or the Home button on older models) will toggle it on instantly. On iPhones with Face ID, that means pressing the side button three times in quick succession, something that happens easily when adjusting your grip, pulling your phone out of a tight pocket, or fumbling to silence a call.
To check whether this is your culprit, go to Settings, then Accessibility, then Accessibility Shortcut. If any hearing-related features are selected there, deselect them. That removes the triple-click trigger entirely.
How It Gets Enabled on Android
On Android phones, RTT settings live inside the Phone app itself rather than in general system settings. Open your Phone app, tap the three-dot menu, go to Settings, then look for Accessibility or a dedicated RTT option. The key setting to watch is the visibility preference: if it’s set to “Always visible,” the RTT button appears on every call screen, making it easy to tap by accident mid-call. Switching this to “Visible during calls” reduces the chance of accidental activation, though on some devices even that keeps a small RTT icon in your call interface.
Samsung devices handle this slightly differently. Navigate to Phone settings, then Accessibility, then Hearing Enhancements, then Real Time Text. Some Samsung models let you toggle RTT off entirely, while others only let you choose between visibility options. If your phone falls into the second category, the best you can do is pick the least intrusive visibility setting.
Software Glitches
Temporary software bugs can also flip RTT on. This is more common right after a major OS update, when new code interacts unpredictably with your existing settings. A simple restart clears most of these glitches by refreshing the system processes that manage call features. If RTT keeps reappearing after a restart, check that your phone’s operating system is fully up to date, since patches for accessibility bugs often arrive in minor updates within weeks of a major release.
If you’ve disabled RTT, restarted your phone, and updated your software but the feature still returns, a network settings reset can help. This clears carrier-level configurations that may be re-enabling RTT. On iPhone, go to Settings, then General, then Transfer or Reset iPhone, then Reset Network Settings. On Android, the path varies by manufacturer but is typically under Settings, then System, then Reset Options. You’ll need to re-enter Wi-Fi passwords afterward, but your apps and files stay intact.
How to Tell RTT Is Active
During a call, RTT reveals itself as a text input field on your call screen. You may also see a small “RTT” label or icon near the call timer. If the person you’re calling also has RTT enabled, anything you type appears on their screen in real time, letter by letter. This can be confusing or alarming if you didn’t intend to activate it, especially since accidental keystrokes during a call get transmitted immediately with no send button required.
If you notice this mid-call, you can typically exit the text interface by tapping the back arrow or the voice call button, though the RTT session may remain technically active until the call ends. To prevent it from happening on your next call, disable the feature using the steps above before dialing again.