If you saw a warning about the bootloader being updated when you installed the May 2026 Pixel update, you're not the only one wondering what it means.
The warning is real and worth understanding before you flash anything custom or factory reset the phone. It applies specifically to the Pixel 10, Pixel 10 Pro, Pixel 10 Pro XL, and Pixel 10 Pro Fold. Here's what changed, why it matters, and what to do.
What Anti-Rollback Means
The bootloader is the small piece of software that runs first when you power on your phone. It checks that the rest of the operating system is signed and trusted, then hands off to Android.
Anti-rollback is a security feature that prevents the bootloader from accepting an older, less-secure version of the operating system. If a flaw is fixed in a newer Android version, anti-rollback stops attackers from forcing your phone back to the buggy version to exploit it.
The May 2026 update incremented the anti-rollback version on Pixel 10 series phones. After you install this update, the phone will refuse to boot any Android 16 build older than the May patch level.
Why It Matters for Most Users
For most people, anti-rollback is invisible. You install updates, the version goes up, and your phone keeps working. The warning matters in two specific scenarios.
The first is if you've ever flashed a custom Android build, GrapheneOS, or any modified system image. Anti-rollback can leave the phone unable to boot back to the stock OS if the active slot fails. Read carefully before sideloading anything after this update.
The second is the A/B slot situation built into modern Pixels. The May update only increments the bootloader on the active slot. If the active slot later fails to boot, the phone falls back to the inactive slot, which still has the older bootloader and can no longer chain into newer signed images. In that scenario the device enters an unbootable state.
The Recommended Action: Sideload the Full OTA
Google's official recommendation is to sideload the full OTA package after the first successful boot into the May 2026 build. That writes the new bootloader and matching image to both A/B slots, eliminating the fallback risk.
Google notes it is generally easier and safer to sideload the full OTA than to flash factory images, because the OTA preserves user data and handles slot management automatically.
The full OTA is published on Google's developer factory image site. The procedure is: enable Developer Options on the phone, enable USB debugging, connect to a computer running ADB, reboot into recovery, and sideload the OTA from there.
If that sounds beyond your comfort level, the safer choice is to wait. Most users will never trigger the unbootable scenario, because the active slot fails extremely rarely. Just be aware that the inactive slot is now in a stale state.
What to Avoid
Do not factory reset the phone without first ensuring both slots are on a compatible bootloader. A factory reset alone doesn't fix the slot mismatch.
Do not flash an older boot image, an older recovery image, or an older system image. Anti-rollback will refuse to boot from it, and you'll be stuck.
If you're running any custom kernel or modified build, check whether your custom variant is compatible with the new anti-rollback version before you reboot.
What to Do If You're Already Unbootable
If your Pixel is stuck because of an anti-rollback mismatch (you'll typically see a verification or rollback-prevented message at boot), the recovery path is to flash via fastboot.
Connect to a computer with the Android SDK Platform Tools installed. Use fastboot to flash a current Android 16 image to both slots. Google's developer site publishes the factory images for each Pixel.
If you don't have the SDK installed or you're not comfortable with fastboot, contact Google Pixel support. They can guide you through it remotely or schedule a service for hardware support.
What Was Actually Fixed in the May Update
Beyond the bootloader change, the May 2026 Pixel update did include two notable fixes. Google patched a wireless charging throttling issue that was capping charging speeds between 75 and 80 percent battery on a wide range of Pixel devices.
Google also fixed a camera freeze that occurred when recording video while adjusting zoom. Both fixes apply broadly across the supported Pixel lineup from the Pixel 7a through Pixel 10 series.
The other major outstanding issue, the GNSS-related idle battery drain, was not fixed in the May update and remains unresolved.
