In general, only the latest backup of iPhone gets stored on iCloud and older backup gets automatically updated and replaced by the new backup.
However, as you switch phones and buy more devices, multiple iOS devices get linked to the same Apple ID and each of these devices will have their own backup file taking up storage space in your iCloud Account.
If you no longer need iCloud Backups of your previous devices, you can free up storage space in your iCloud Account by deleting those unwanted iCloud Backups.
Delete iCloud Backups on Mac
If there are unwanted Backups of iPhone and other Apple devices laying in your iCloud Account, you can find below the steps to delete iCloud Backups by using Mac and Windows computer.
1. Delete iCloud Backups on Mac
Follow the steps below to delete iCloud Backups on Mac.
1. Click on Apple Logo in top-menu bar and click on System Settings in the drop-down menu.
2. On System Preferences screen, click on iCloud.
Note: You may be prompted to Login to iCloud using your Apple ID and Password.
3. On iCloud screen, click on the Manage button.
4. On the next screen, click on Backups in the left pane. In the right-pane, select the iCloud Backup that you want to delete and click on the Delete option.
5. On the confirmation pop-up, click on the Delete button to confirm.
The selected iPhone Backup will be immediately deleted from your iCloud Account.
2. Delete iCloud Backups on Windows Computer
You can follow the steps below to delete iCloud Backup on a Windows computer.
1. Click on the Start button > scroll down the list of Apps and click on iCloud.
2. Login to your iCloud Account by entering your Apple ID and Password.
3. On iCloud screen, click on Storage.
4. On Manage Storage screen, click on Backups in left pane. In the right pane, select the iPhone Backup that you want to delete and click on Delete.
5. On the confirmation pop-up, click on Delete to confirm.
The selected iCloud Backup will be deleted from your iCloud Account.