Learn what to do if your Mac’s Contacts app is full of duplicate entries after updating your computer to a newer version of macOS.

Have all of your Contacts suddenly been duplicated after updating your Mac to macOS Big Sur or later? If so, you’re not alone.
You can certainly go through the process of removing the duplicates, as some have suggested in the Apple Community forum. But there is another suggestion, used by our own Sebastien Page, that is the quickest and easiest way to go.
Basically, you’ll restore your Contacts to the last backup in iCloud, and it will get rid of all the duplicates.
You can restore your contacts from your Mac, iPad, or iPhone, provided they all use the same Apple ID and Contacts is enabled in iCloud settings.
Restore Contacts on iCloud
1) Visit iCloud.com and sign in with your Apple ID credentials.
You can log in to iCloud in Safari and authenticate simply by using your Face ID, Touch ID, or device passcode instead of your Apple ID password.
2) Scroll down to the bottom of the iCloud web screen and click Data Recovery.
3) Select the Restore Contacts tile.
4) Click Restore next to an archive to restore. Obviously, you’ll want to choose the last one backed up before you upgraded your Mac.
Tip: You can see the exact date when macOS was last updated on your Mac.
5) Confirm the action by clicking Restore in the subsequent pop-up.
Once you restore the archive, the duplicates should be gone, and your Contacts list should be intact from the backup you picked.
Hopefully, this short how-to has your contacts back where they belong without those duplicates. And if you’ve run into other issues since upgrading, let us know in the comments below!
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