Google has quietly linked SIM phone numbers across all signed in Google accounts on Android devices by default since late 2025 to enable features.
According to Engadget, Android phones have been attaching their SIM card phone numbers to every signed-in Google profile on the same device for over a year. The automatic verification feature was quietly put into place in September 2025, operating automatically during device setup. Support documentation from Google states that the process covers work profiles, secondary accounts, and any future accounts added to the device. Furthermore, swapping out a SIM card automatically adds the new number to every profile currently signed into the handset.
Engadget reports that users are only now discovering the behavior after receiving unprompted confirmation emails from noreply-phone-verification at google dot com. Google explains that the automatic linking supports several core platform features, including account recovery, emergency location services, device tracking, Quick Share, and Rich Communication Services messaging. Additionally, the system enables Better sharing features across accounts for video calls and notifications, while certain support pages also mention a Better ads and Google services setting that utilizes the verified digits to serve more relevant advertising.
Periodically, Google and mobile carriers re-verify these numbers, a process that can potentially incur carrier charges for users. Managing the feature requires physical access to the device. Users who wish to halt the automatic linking can navigate to device settings, select Google or Google services and preferences, open Privacy and security, choose Phone number verification, and toggle off the automatic verification setting. However, Engadget notes that disabling this option does not remove numbers that were already attached, meaning users must manually delete them from the personal information settings of each individual Google account.
Kaspersky points out that turning off the verification feature carries notable trade-offs, such as losing RCS chats in Google Messages and reverting conversations back to standard SMS, alongside forfeiting quick account recovery options. Google maintains that it does not sell personal data, including phone numbers, to outside parties. Additionally, tests in select regions show that new accounts may receive only 5GB of free storage rather than the standard 15GB unless a phone number is linked.
Background
The automatic number verification process was uncovered when Android Authority examined changes made to Google documentation between August and October 2025, alongside a Google Play services changelog published on September 8, 2025. In October 2025, Google launched Sign in with Mobile Number, a recovery tool allowing users to access accounts via a previous device lock screen passcode. In May, Google also began testing a policy requiring a linked phone number for new accounts to maintain the standard 15GB storage tier.
What This Means
The silent linking of phone numbers highlights the fine line tech giants walk between seamless functionality and user transparency. While automatic verification enables modern communication standards like cross-platform RCS and rapid device recovery, doing so across every secondary and work profile without explicit upfront prompts risks eroding user trust. As privacy regulations tighten globally, the burden placed on users to manually audit and reverse default settings could invite closer regulatory scrutiny regarding how large platforms bundle ecosystem features.
Illustration: AI-generated image, not a photograph of the event.