WhatsApp backup stuck? 9 fixes for iPhone and Android

A WhatsApp backup that sits on Preparing, stops at a percentage or fails overnight is a common worry, especially before switching phones. Your chats are still on your phone while this happens, but without a finished backup they cannot be restored if the phone is lost or reset. The fix is almost always one of three things: not enough space, a cloud account problem, or a connection or battery setting that stops the upload. Below, we explain how the backup works, then go through the fixes in order, with separate checks for iPhone and Android, and finally the cases where you can skip the cloud backup entirely.

How WhatsApp backup works

• iPhone: backs up to your iCloud Drive, using your iCloud storage.
• Android: backs up to the Google account selected in WhatsApp, using your Google storage.
• Two stages: first WhatsApp prepares a backup file on the phone, which needs free phone storage, then it uploads it, which needs cloud space and a steady connection.
• Separate from your phone backup: the iPhone or Android device backup does not replace WhatsApp’s own backup.

How to fix a stuck WhatsApp backup

Check when the last backup finished

Open WhatsApp › Settings › Chats › Chat backup. The screen shows the date and time of the last successful backup and its size. If the date is recent, your chats are protected even if today’s backup is stuck. The size also tells you how much free space you need: on iPhone, WhatsApp asks for at least 2.05 times that amount free, both on the phone and in iCloud.

Set an automatic schedule

In the same Chat backup screen, set Auto Backup to Daily or Weekly. Daily backups happen in the background, usually overnight when the phone is charging and on Wi-Fi, and each one only adds what changed, so they are smaller and less likely to stall than an occasional huge backup. If you set it to Off, you have to remember to back up yourself, which is easy to forget until it is too late.

iPhone checks

• Go to Settings › [your name] › iCloud and make sure iCloud Drive is on.
• In the same screen, under apps using iCloud, make sure WhatsApp is turned on.
• Check you are signed in to the same Apple Account you want the backup in.
• Update iOS, since older versions can have iCloud Drive upload bugs.
• If your iCloud storage is full, free space or upgrade before trying again. See what to do when iCloud storage is full.

Android checks

• In WhatsApp › Settings › Chats › Chat backup, tap Google Account and make sure the right account is selected.
• Check that account’s storage at one.google.com/storage, since WhatsApp backups now count toward it.
• Update Google Play services and WhatsApp from the Play Store.
• If backup over cellular is off, connect to Wi-Fi; if it is on, remember a large backup can use a lot of mobile data.

Make the backup smaller

The bigger the backup, the more likely it is to stall. Open WhatsApp › Settings › Storage and data › Manage storage. Review items larger than 5 MB and the chats using the most space, and delete videos and files you do not need. Group chats full of forwarded videos, memes and voice notes are usually the biggest culprits. Turning off Include Videos in Chat backup can cut the backup to a fraction of its size; your videos stay on the phone, they just are not in the backup.

Battery, data and VPN settings

• Turn off Low Power Mode on iPhone, or battery saver on Android, while the backup runs.
• On Samsung, make sure WhatsApp is not in Sleeping apps, in Settings › Battery › Background usage limits.
• Turn off VPNs and data saver modes while backing up, since both can stall the upload.
• Keep WhatsApp open with the screen on for the first large backup, and plug the phone into a charger.

End-to-end encrypted backups

In Chat backup, you can turn on End-to-end encrypted backup, protected by a password or a 64-digit key. It keeps the backup private even from Apple, Google and WhatsApp itself, which is a real privacy benefit. The catch: if you forget the password or lose the key, WhatsApp cannot recover the backup for you. Write the password down and keep it somewhere safe at home. If an encrypted backup keeps failing, you can turn encryption off and on again, which creates a new backup.

Common error messages

• “Couldn’t complete backup” or “Backup failed”: usually space or connection. Free space on the phone and in the cloud, then try on strong Wi-Fi.
• “Not enough storage”: check both phone storage and iCloud or Google storage; either can be the one that is full.
• “Sign in to iCloud” or no Google account: the cloud account is signed out or not selected. Sign in again in Settings or WhatsApp’s backup screen.

Switching phones? You may not need the cloud

Between two iPhones or two Android phones, WhatsApp can transfer chats directly. On the old phone, open WhatsApp › Settings › Chats › Transfer chats, and scan the QR code shown on the new phone while both are on the same Wi-Fi. It skips the cloud backup entirely and is often faster for big chat histories. Android users also have a local backup file on the phone, which WhatsApp creates daily in its media folder, and which some people copy to a computer as an extra safety net.

Still stuck after everything?

Deleting the old cloud backup does not touch the chats on your phone, but for a short while you will have no backup at all, so only do it when the phone is safe at home.

Restoring the backup later

To restore, install WhatsApp on the new or reset phone, verify the same phone number, and sign in to the same iCloud or Google account that holds the backup. WhatsApp finds it and offers Restore during setup. Moving between iPhone and Android uses a different path, not the cloud backup; see how to move from Android to iPhone. WhatsApp Business has its own separate backup, so back it up too if you use both apps.