Since September 2025, Android phones check phone numbers automatically during setup. They add the number to every Google account on the phone, including work accounts. Google says this helps people get back into their accounts and use messaging tools. Some people only recently learnt about this through emails from Google.
The setting also covers accounts you add later. If you change your SIM card, Android adds the new number to all your accounts. Google and your phone company check the numbers again from time to time. Your phone company may charge for these checks.
You can only change this setting on the phone itself. Open Settings, then Google, then All services. Under Privacy & security, choose Phone number verification and switch off Verify phone numbers automatically. On some phones, the Google section has the name Google services and preferences.
Switching this off does not remove numbers already in your accounts. For each account, open its Google settings, then Personal info and Phone, and remove the number yourself. Security company Kaspersky says switching it off stops RCS, a service for chats in Google Messages, so chats use basic SMS text messages instead. It also says you cannot use that number to get back into your account quickly.
