Why won't my smartwatch sync with my phone after an update?

Software updates on either the phone or smartwatch can change Bluetooth protocols or app permissions. After an update, re-pair the devices by forgetting the Bluetooth connection and reconnecting through the companion app. Also ensure the app has all required permissions (location, notifications, background refresh). If the issue persists, check for a smartwatch firmware update in the app settings.

How do I fix Bluetooth pairing issues between my smartwatch and phone?

Start by turning Bluetooth off and on again on both devices. Make sure the smartwatch is in pairing mode (usually found in settings). Delete any old pairings from the phone's Bluetooth list. Restart both devices. If that fails, reset the network settings on your phone (this won't delete personal data but will remove saved Wi-Fi and Bluetooth connections). For persistent issues, try pairing in a different location away from interference.

Should I factory reset my smartwatch if it won't sync?

A factory reset should be a last resort. Before resetting, try unpairing the watch from the app, reinstalling the companion app, and checking for updates. If you must reset, back up any data first (if supported). On Apple Watch, use the Watch app on iPhone to unpair (which backs up automatically). On Samsung, use the Galaxy Wearable app. After reset, set up the watch as new and re-pair. Note that a reset erases all personal data.

Can a low battery on my smartwatch cause syncing problems?

Yes, a low battery can interfere with Bluetooth communication. Ensure your smartwatch has at least 30% charge before attempting to sync. Some watches, like the Apple Watch, may disable certain features when battery is critically low. Charge the watch fully and then try syncing again.

Why does my smartwatch sync only when the companion app is open?

This is often due to background app restrictions. On iOS, go to Settings > General > Background App Refresh and enable it for the companion app. On Android, go to Settings > Apps > [Companion App] > Battery and select 'Unrestricted' or 'Optimize for background activity'. Also disable battery optimization for the app. This allows the app to sync data even when not actively in use.

Smartwatch Not Syncing with Phone: Troubleshooting Guide

Published July 18, 2026 · Reviewed by the Unbiased Advice & Insights editorial team · How we research and score

Quick answer

Check Bluetooth is on, restart both devices, update the companion app, and ensure all permissions are granted. If still stuck, unpair and re-pair the watch.

Why Your Smartwatch Won't Sync: Common Causes

Smartwatch syncing issues can stem from several sources. The most frequent culprit is a disrupted Bluetooth connection, often caused by interference, distance, or the phone being in power-saving mode. Outdated software on either device can also break the link. App permissions that are too restrictive may prevent data exchange. For example, on iOS, the companion app needs Bluetooth and background app refresh enabled. On Android, location permission is often required for Bluetooth scanning. Battery optimization settings can kill background processes, halting sync. Finally, a glitch in the watch's firmware or the phone's Bluetooth stack can cause intermittent failures. Interference from other wireless devices like Wi-Fi routers, microwaves, or even other Bluetooth devices can degrade the signal. Physical obstacles such as walls or metal objects between the phone and watch can also reduce range. Additionally, if your phone is in low-power mode, it may disable Bluetooth scanning or background data to save battery, preventing sync. On some Android phones, the 'Data Saver' feature can restrict background data for the companion app, so check that too.

How to Fix Smartwatch Syncing Issues: Step by Step

Restart both devices. A simple restart clears temporary glitches. Turn off the smartwatch and phone, wait 30 seconds, then power them back on. This often resolves minor Bluetooth hiccups. For watches with a touch screen, you can usually restart from the settings menu; for others, press and hold the power button. On phones, a full restart (not just sleep) is recommended.
Check Bluetooth and app permissions. On your phone, go to Bluetooth settings and ensure it is on. Forget any old smartwatch pairings. Then open the companion app (e.g., Apple Watch app, Galaxy Wearable, Fitbit, Garmin Connect). Verify that all required permissions are granted: location (for Android Bluetooth scanning), notifications, and background data. On iOS, ensure Background App Refresh is enabled for the app. On Android, go to Settings > Apps > [App] > Permissions and enable Location (while using the app) and Nearby Devices if available. Also check that the app is allowed to run in the background under Battery settings.
Update software. Outdated software is a common cause. On the phone, install the latest OS update. Also update the companion app from the App Store or Google Play. For the smartwatch, check for firmware updates in the app's settings (e.g., Apple Watch: Watch app > General > Software Update; Samsung: Galaxy Wearable > Watch settings > About watch > Update watch software; Fitbit: Fitbit app > Account > [Device] > Firmware Update; Garmin: Garmin Connect > [Device] > System > Software Update). Make sure both devices are on the same major version if possible.
Unpair and re-pair. In the companion app, choose to unpair or disconnect the watch. This removes the Bluetooth bond. Then restart both devices again. Put the watch in pairing mode and follow the app's setup process to pair fresh. For Apple Watch, use the Watch app to unpair (which backs up the watch). For others, you may need to factory reset if unpairing doesn't work. When re-pairing, keep the phone and watch close together (within 3 feet) and avoid other Bluetooth devices.
Reset network settings (phone). On Android: Settings > General management > Reset > Reset network settings. On iOS: Settings > General > Transfer or Reset iPhone > Reset > Reset Network Settings. This clears all Wi-Fi and Bluetooth connections but not personal data. After reset, re-pair the watch. Note that you will need to re-enter Wi-Fi passwords and re-pair other Bluetooth devices.
Factory reset the smartwatch (last resort). If nothing else works, reset the watch. On Apple Watch: Settings > General > Reset > Erase All Content and Settings. On Samsung Galaxy Watch: Settings > General > Reset. On Fitbit: Settings > About > Factory Reset. On Garmin: Settings > System > Reset. After reset, set up as new and pair again. Note that this erases all data; back up if possible. For Apple Watch, the backup is automatic when unpairing via the Watch app. For others, check if the companion app offers a backup option before resetting.

When to Replace Your Smartwatch

If you've tried all steps and the watch still won't sync, it may be time to consider a replacement. Signs that replacement is warranted: the watch is several years old and no longer receives firmware updates, the battery drains rapidly even after a reset, or physical damage (cracked screen, broken buttons) is present. For budget-friendly options, look at current models from Fitbit or Amazfit. For premium experiences, consider the latest Apple Watch or Samsung Galaxy Watch. Check the current price on Amazon for the best deals. Always verify compatibility with your phone's OS before purchasing. Also consider that some older watches may have outdated Bluetooth versions that are less reliable with modern phones. If your watch is more than 3-4 years old, a new model will likely offer better connectivity and longer battery life.

Preventing Future Syncing Issues

To avoid recurring syncing problems, follow these best practices. Keep both your phone and smartwatch updated with the latest software. Regularly check for app updates in the app store. Avoid letting your watch battery drain completely, as this can sometimes cause the Bluetooth stack to reset. When not using Bluetooth, turning it off and on again can refresh the connection. If you frequently switch between phones (e.g., work and personal), unpair the watch from the old phone before pairing with the new one. Also, periodically clear the Bluetooth cache on your phone: on Android, go to Settings > Apps > Show system apps > Bluetooth > Storage > Clear cache. On iOS, there is no direct cache clear, but restarting the phone helps. Finally, if you experience intermittent sync failures, try moving the phone and watch closer together or away from other electronic devices.

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