You might want to transfer iPhone backup files when you copy data from an old computer to a new computer, like from Windows to Windows, from Windows to Mac, from Mac to Windows. Here will show you how to transfer iTunes backup files in those situations.
How to Transfer iPhone Backups from Windows to Windows Computer
In fact it is very easy to do that, what you need is an old computer with your backup files, another computer you want to store your backup files, and a USB drive.
First you need to find iTunes backup folder on Windows computer:
Windows Vista, Windows 7, Windows 8, Windows 10: \Users\(username)\AppData\Roaming\Apple Computer\MobileSync\Backup\
Windows XP: \Documents and Settings\(username)\Application Data\Apple Computer\MobileSync\Backup\
If you can't find the iPhone backup files based on the path above, the file you looking for could have been moved, you can search "AppData" on your computer to locate the iTunes backup files.
Then insert a flash drive into your old computer and copy the iTunes backup files to the flash drive.
Now you can paste the iPhone backup files to the new Windows computer with the flash drive. But you have to install the iTunes on your new computer first, then paste the files to the corresponding location.
If you want to transfer iPhone backup files from Windows to Mac or from Mac to Windows, you need to know the iTunes backup folder location on Mac: ~/Library/Application Support/MobileSync/Backup/. The “~” represents your Home folder. After that, you can transfer iPhone backup files from old PC/Mac to new PC/Mac step by step same as the guide above.
After transfer iPhone backup files to another computer, you can manage your iPhone backup files in the new computer. Hope this guide can help you.