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How Google phone number verification works, and whether you should turn it off | Kaspersky official blog
Starting last year, Android users have been seeing the “number is now verified” system notification more frequently. And in some cases people even find mysterious outgoing text messages in their history that they never sent.
These messages often cause confusion and even anxiety: has a virus infected the phone? Are tech giants spying on our phone numbers? Let’s break down how this feature works, and what potential risks it poses to your privacy.
Why all these phone number verifications?
The notification pops up whenever Google’s phone number verification feature is triggered on your device.
Its main job is to make sure that the SIM card tied to a specific phone number is physically inside the phone. Once verified, that phone number automatically links to all active Google accounts on the device.
There are several key services that rely on the verification. Most importantly, it drives Rich Communication Services (RCS) — the modern standard for “rich” messaging right inside your standard text messaging app. It feels like a popular chat app, but without the need to install anything extra. Unlike iMessage, which is locked to Apple’s ecosystem, RCS works across compatible smartphones on various platforms since it’s an industry standard set by carriers rather than tech giants. Since recently, both Apple and Android users have been able to exchange RCS messages. For this feature to work in the Google Messages app, Google needs ongoing confirmation that your SIM card is active. If you pull out your SIM card, RCS chats will keep working for about eight days before turning off automatically.
According to Google, phone number verification serves several other purposes as well:
- Account security and recovery. A verified phone number enables quick sign-ins to your Google account, two-factor authentication, and easy password recovery.
- Emergency services and device location. This includes Find My Device, remote phone lock, and sharing your location with emergency responders — including via satellite messaging on the Pixel 9 and certain other modern smartphones.
- Better sharing on Google. This feature helps other people find you faster on Google Meet or Duo, use Quick Share to send you files, and see that the phone number is linked to your profile.
Google also recently confirmed that this data is used to counter scams. Verification helps block calls or text messages from spoofed numbers if both the real owner of the number and the recipient are using Android devices with verified phone numbers.
How does Google verify phone numbers?
Phone number verification technology has been around on Android for quite some time — Google was sending test SMS messages as far back as in 2019. However, it became widely visible to most users following a Google system update in September 2025. The process was baked deeper into the operating system, with number verification now running by default during initial phone setup, and re-running periodically in the background.
There are two main technical methods for the verification process. Which one your device uses depends on your mobile carrier and your version of Android.
The older method relies on hidden text messages. In the background, your smartphone sends a specialized technical text message to Google’s servers. The operating system intercepts this message before you ever see it, which is why it rarely appears in your standard text messaging app. However, due to software glitches or Android customization quirks, these texts occasionally surface in sent messages, startling users. They typically look like this: “(string of letters and numbers) Google is re-verifying the phone# of this device.” Google explicitly notes in its help documentation that standard messaging rates from your carrier may apply.
In recent years, direct carrier verification (via carrier APIs) has become the primary verification method. This approach is more modern and secure than previous ones. The smartphone sends an encrypted token containing device and SIM card identifiers to the mobile carrier, and the carrier responds with the confirmed phone number. The whole process takes just a couple of seconds and runs completely unnoticed by the user. Both global telecom giants and smaller providers have connected to this verification network. Notably, third-party apps can also tap into the results of this check through Firebase Phone Number Verification, getting confirmation from your mobile carrier about which phone number is active on the device.
“Other device data” and privacy concerns
In its official documentation, Google notes that device identifiers and SIM card data may be collected during verification. In practice, this refers to unique identifiers for the SIM card and its subscriber profile (ICCID and IMSI), as well as technical device identifiers needed to run mobile networks. Google also explicitly states that it does not sell your personal information, including your phone number, to anyone.
Naturally, sending additional unique identifiers to Google — especially given the scale of its advertising business — always raises concern among privacy-conscious users. Here’s what you should keep in mind:
Metadata collection. To run RCS, Google exchanges data with your mobile carrier. Even when the content of RCS messages is encrypted, metadata — such as who is messaging whom and when — can still be stored on your carrier’s servers, and in some cases, on Google’s servers. As cybersecurity experts at the Electronic Frontier Foundation point out, if privacy is your top priority, you’re better off sticking to dedicated encrypted messaging apps.
Linked accounts. If you have both a personal and a work Google account (or a personal and a family account) set up on the same phone, the verified number will automatically link to both profiles. The operating system does not offer built-in tools to separate numbers for different accounts on a single device.
Phone number leaks. Apps on your device can already access various user identifiers, including your phone number. However, this verification system makes it easier to link multiple phone numbers to a user who has multiple Google accounts. And while Google states that it never sells phone numbers, you cannot say the same with confidence about obscure third-party Android developers.
On by default. The feature is enabled out of the box, and most users have no idea their device is silently querying their carrier in the background. While you can opt out in your Google settings once you notice it, there’s no guarantee that any data already collected will actually be deleted.
Turning off verification — why and how
For most users, verification is genuinely helpful. It simplifies account recovery, makes finding a lost phone easier, powers modern text messaging features, and assists emergency services when every second counts.
However, if you want to minimize the amount of metadata sent to Google, mobile carriers, and other data brokers, you can manually disable the feature. Here’s how:
- Open your Android smartphone’s settings.
- Tap Google, select the account at the top, and switch to the All services tab.
- Under Privacy and security, tap Phone number verification.
- Turn off automatic phone number verification.
If you also want to disable Better sharing on Google, go to Settings → Google → Manage your Google Account → Personal info → Contact info → Phone, select your number, and turn off the setting.
If you have multiple Google accounts on your phone, you’ll need to repeat these steps for each one. Unfortunately, verification sometimes turns itself back on automatically, and there’s no reliable way to prevent this on standard consumer phones with stock software.
Keep in mind that disabling verification means losing access to RCS chats in Google Messages — forcing you to fall back on basic SMS, or switch to alternative secure messaging apps. You also won’t be able to use that number for quick account recovery should you forget your password.
To thoughtfully customize your privacy settings across all your devices — regardless of the operating system, browser, or app — check out our free online tool, Privacy Checker.
Curious about other privacy risks you might not even know exist? Check out our other deep dives, here:
