Summary
This setting has been in place by default since September 2025. Android phones have been attaching their SIM's phone number to every signed-in Google …
Android phones have been attaching their SIM's phone number to every signed-in Google account on that device for more than a year. Google's support documentation says that it verifies the number automatically during setup and adds it to every account on the phone, including work and secondary accounts. According to Google, verification enables features like account recovery and RCS messaging, but the company doesn't explain why the number needs to be added to every account.
Android Authority found that the Google documentation in question was amended sometime between August and October 2025 to say that verification is on by default, while a Google Play services changelog dated September 8, 2025 lists number verification as running automatically on setup. However, plenty of folks are only now finding out, after unprompted emails from [email protected] began arriving to tell them their number had been verified.
What Google does with linked numbers
According to Google's support page, the link covers existing and future accounts and numbers alike. In other words, a Google account that's added later will pick up every number on the phone, while switching SIM cards also puts the new number on every account. Google and your carrier also re-verify those numbers periodically, which can incur carrier charges, and the setting can only be managed from the phone itself.
It's a bit of an awkward situation, because turning verification on also enables Better sharing on Google for one of the signed-in account. Google says this supports video calls, messages and notifications for content sent to the number, such as photos. Phone number sign-in, finding a lost device, emergency location services and Quick Share also all depend on a verified number.
In October 2025, a month after automatic verification arrived, Google introduced Sign in with Mobile Number, an Android recovery tool that auto-identifies the Google accounts linked to a phone number and lets the owner back in with the lock screen passcode from their previous device. Google's account help pages also describe a Better ads & Google services setting that uses a phone number across Google services to show more relevant ads.
The same page says that any verified number on an Android device can be added to any Google account signed into it, though Google hasn't said which ads setting applies to numbers attached automatically.
How to turn off phone number verification
To stop the linking on your Android phone, open Settings > Google > All services, then under Privacy & security, select Phone number verification and turn off Verify phone numbers automatically. Some phones will label the Google section Google services and preferences instead.
Keep in mind that turning this off doesn't apply retrospectively, meaning numbers that have already been attached must be removed manually. You can do this by navigating to Personal info > Phone in each account's Google settings.
Kaspersky says disabling verification also means losing RCS chats in Google Messages, which pushes conversations back to SMS. Google's Messages help pages show RCS waits on phone number verification before it connects. That trade-off carries more weight, since end-to-end encrypted RCS messaging began rolling out between Android phones and iPhones in May. Kaspersky adds that a number with verification turned off can't be used for quick account recovery.
Google says it doesn't sell personal data, including phone numbers, to anyone. In May, it also told Android Authority it was testing a policy in select regions that gives new Google accounts only 5GB of free storage unless a phone number is linked, down from the usual 15GB.
Source: Engadget
