If you have accidentally deleted or lost your WhatsApp chat history, you can restore it. WhatsApp automatically saves your chats from the last seven days by creating a backup every night at 2 a.m., which is simply saved on your own phone. It is also possible to set your phone to copy your chats to the cloud. If you only want to restore deleted chats from the most recent backup and you already had your information copied to the cloud, the easiest way is to uninstall and reinstall the app. However, because your device stores nightly backups up to seven days back, you can also go back to a specific day in the last week.
Steps
Method 1 of 3: Restore your last backup

Step 1. Make sure your lost data is backed up
Do not create a new backup at this time, as it will overwrite the most recent version of your backup, so you will lose the deleted messages in the backup as well.
- Open WhatsApp and tap Settings.
- Tap Chats and Backup chats.
- Look at the Last backup date and time. If the backup in question should include the messages you want to restore, continue with this method. If not, try one of the other methods.

Step 2. Remove WhatsApp from your phone
Before you can recover deleted messages, you must uninstall the entire app.

Step 3. Go to the app store on your phone and download WhatsApp again

Step 4. Launch the app from the home screen

Step 5. Agree to the terms
Then enter your mobile phone number.

Step 6. Recover your messages
The next screen will let you know that a backup copy of your messages for your phone has been found. Click "Restore" and wait for the restore process to complete.
By default, WhatsApp backs up all your message threads every day at 2 a.m. The last backup created is loaded
Method 2 of 3: Restore a less recent backup on Android

Step 1. Open the App Drawer
By default, your phone has backup files from the last seven days, while Google Drive only keeps the most recent.

Step #2. Tap File Manager

Step #3. Tap sdcard

Step #4. Tap WhatsApp

Step 5. Tap Databases
If your data isn't on your SD card, it could also be in your phone's internal storage.

Step 6. Rename the backup you want to restore
Rename msgstore-YYYY-MM-DD.1.db.crypt12 to msgstore.db.crypt12.
Older backups can also be on a different protocol such as crypt9 or crypt10

Step 7. Uninstall WhatsApp

Step 8. Reinstall WhatsApp

Step 9. Tap Restore
Method 3 of 3: Restore a less recent backup on iOS

Step 1. Download File Manager from App Store

Step 2. Install it on your phone

Step #3. Open File Manager

Step #4. Tap sdcard

Step 5. Tap WhatsApp

Step 6. Tap Databases
If your data isn't on your SD card, it could also be in your phone's internal storage.

Step 7. Rename the backup you want to restore
Rename msgstore-YYYY-MM-DD.1.db.crypt12 to msgstore.db.crypt12.
Older backups can also be on a different protocol such as crypt9 or crypt10

Step 8. Uninstall WhatsApp

Step 9. Reinstall WhatsApp

Step 10. Tap Restore
Tips
- The option to fully restore a deleted chat history is only a feature on the Blackberry 10.
- It may take a while for your first backup to complete. To prevent your phone from turning off in the middle of the backup, it's a good idea to connect the phone to a power source.
- Do not make a manual backup after a message has been accidentally deleted. This replaces the old backup file (containing the thread you want to restore) with a new one.