How to Fix Gmail Not Syncing on Android and iPhone
What Gmail sync errors means
A Gmail sync error means the Gmail app on your phone has stopped exchanging data with Google's servers. New emails do not arrive, sent mail sits in the outbox, and you may see a "sync is currently experiencing problems" notice or a spinning refresh that never finishes. Your mail itself is safe on Google's servers — the problem is purely the connection between the app and the server.
Sync failures usually come down to a short list of causes: sync was accidentally turned off, the app's cached account data became corrupted, the phone is blocking Gmail's background activity to save battery or data, or the device is so full that the app cannot write new messages. Because the causes live in different settings screens, the fix is a checklist you work through top to bottom.
Common causes
- Sync turned off: the Gmail or Google-account sync toggle got disabled — by an update, a settings change, or battery-saver mode.
- Corrupted app cache or data: damaged local account data makes the app fail every sync attempt.
- Battery optimization and data restrictions: aggressive power saving or Data Saver blocks Gmail from syncing in the background.
- Full device storage: with no free space, the app cannot download or store new messages.
- Outdated app or account glitch: an old Gmail version or a stale login token breaks the sync handshake with Google's servers.
How to fix Gmail sync errors — step by step
Work through these fixes in order. Most sync problems are fixed by step 1 or 2.
- Verify Gmail sync is enabled. On Android, open the Gmail app, tap the menu, then Settings, then your account, and make sure Sync Gmail is checked. Then go to your phone's Settings, then Accounts (or Passwords & accounts), then Google, then your account, and confirm Gmail is toggled on in the sync list. On iPhone, go to Settings, then Mail, then Accounts, then your Google account, and make sure Mail is on. Then go to Settings, then Mail, then Accounts, then Fetch New Data, and set it to Push at the top with your Google account set to Push below.
- Clear the Gmail app cache. On Android, open Settings, then Apps, then See all apps, then Gmail, then Storage & cache, and tap Clear cache. This removes corrupted temporary sync data without touching your emails. Reopen Gmail and pull down to refresh. On iPhone, iOS does not offer per-app cache clearing: go to Settings, then General, then iPhone Storage, then Gmail, tap Offload App, then Reinstall App. If sync still fails, return to the same screen and choose Delete App, then reinstall Gmail from the App Store and sign in again.
- Check battery, background, and data restrictions. On Android, go to Settings, then Apps, then Gmail, then Battery, and set it to Unrestricted (or turn off Battery optimization for Gmail). In the same Apps screen, tap Mobile data & Wi-Fi and make sure Background data is allowed. If Data Saver is on (Settings, then Network & internet, then Data Saver), either turn it off or allow Gmail unrestricted data usage. On iPhone, go to Settings, then General, then Background App Refresh, and make sure it is on for Gmail; also confirm Low Data Mode is off under your Wi-Fi or cellular settings.
- Free up storage space. Open Settings, then Storage, and check how much free space you have. If the phone is nearly full, Gmail cannot download new messages. Delete unused apps, clear old downloads, move photos to cloud backup, and empty the trash. Aim for at least 1 GB of free space. After freeing space, restart the phone and open Gmail to trigger a fresh sync.
- Remove and re-add your Google account. This rebuilds the sync relationship from scratch. On Android, go to Settings, then Passwords & accounts, then your Google account, and tap Remove account. Restart the phone, then go back to Settings, then Passwords & accounts, then Add account, then Google, and sign in again. On iPhone, go to Settings, then Mail, then Accounts, then your Google account, tap Delete Account, restart, and add it back via Add Account, then Google. Open Gmail, wait a few minutes, and check whether new mail arrives.
- Update Gmail and check Google's status. Open the Play Store or App Store, search Gmail, and install any update — sync bugs are regularly fixed in new releases. Also update Android System WebView on Android, since Gmail depends on it. Finally, rule out a Google-side outage: if Gmail will not sync on any device and the web version at mail.google.com is also failing, check Google Workspace Status Dashboard. If Google is down, the only fix is to wait.
Did this fix it? Quick checklist
- New emails arrive within a minute or two
- Sent mail leaves the outbox promptly
- No "sync is currently experiencing problems" notice
- Sync still works after locking the phone for 10 minutes
If sync works on Wi-Fi but not on mobile data (or vice versa), your carrier or network may be throttling or blocking Google's sync servers — try a different network to confirm. Corporate or school Google Workspace accounts can also be restricted by an administrator; in that case only your IT admin can re-enable sync. And if one specific label or folder will not sync, open Gmail, then Settings, then your account, then Manage labels, and check the sync settings for that label.
Frequently asked questions
Why did Gmail suddenly stop syncing?
The most common triggers are a system or app update that reset the sync toggle, battery-saver mode blocking background activity, a corrupted app cache, or the phone running out of storage. Work through the steps above in order — the cause is almost always one of these.
Will removing my Google account delete my emails?
No. Your emails live on Google's servers, not on the phone. Removing and re-adding the account only deletes the local copy; everything re-downloads when you sign back in. Drafts that were never synced could be lost, so let any pending send finish first.
Why does Gmail sync on Wi-Fi but not on mobile data?
That points to a data restriction: Data Saver, a carrier data limit, background-data blocking for Gmail, or Low Data Mode on iPhone. Check the settings in step 3, and test with Data Saver off to confirm.
How long should Gmail sync take after these fixes?
Usually a few minutes. After re-adding an account or clearing data, Gmail must re-download your recent messages, which can take 5 to 15 minutes on a large mailbox. Give it time before deciding a fix did not work.