How to clean up your contacts after switching phones

By Michael, founder of ContactAttic · September 2026 · 8 min read

You set up the new phone, the transfer says "done," and then you open Contacts: half your friends are listed twice, some three times. One copy has their mobile, another has their email, a third has a work number they left behind two jobs ago. Nothing is broken, exactly — but the address book you just carried over is a mess. Here's why a phone switch multiplies your contacts, what the built-in fixes actually catch, and how to end up with one clean card per person.

Why a new phone doubles your contacts

The duplicates aren't a bug in the transfer — they're what happens because your contacts never lived in just one place to begin with. A phone switch pulls from several sources at once and stacks them all onto the new device:

• SIM contacts. The handful of numbers saved to the SIM card get copied over with the number and often nothing else — no email, no last name.
• The old phone's local contacts. Cards saved to the device itself, rather than to an account, come across as their own separate set.
• A Google or iCloud account. Signing back into your account re-syncs its full copy of everyone — which overlaps heavily with what the SIM and local import already added.
• Apps that write their own cards. WhatsApp and similar apps create contact entries of their own, so the same person can arrive again from yet another direction.

Because each source carries a different subset of the details, the same person shows up two or three times, and no single one of those cards is complete: one has the mobile, one has the email, one has that old work number. The information is all real and worth keeping — it's just scattered. That's what makes a phone-switch mess harder to clean than an ordinary duplicate: you can't simply delete the extra copies, because each one holds a detail the others don't. Delete the wrong card and you lose the only place a number or address was recorded.

What the built-in cleanup does — and where it stops

Both phone platforms ship a duplicate fixer, and it's worth running first:

• iPhone. Open Contacts; when iOS spots overlaps it shows a "Duplicates Found" banner, and you can Link Contacts to combine a pair into one merged card.
• Android / Google Contacts. In the Contacts app or at contacts.google.com, the Merge & fix panel finds likely duplicates and merges them in bulk.

These help, but they share three limits — and after a phone switch you hit all three. First, they only catch near-identical names: the SIM copy that's just a first name and a number, or a card where the name is spelled a little differently, slips past. Second, each keeps the merge locked inside one account — the fix you run in Google doesn't touch your iCloud copies, and vice versa. Third, neither reconciles across iCloud, Google and any exports at once, so if your people are split between accounts the cross-account doubles simply survive.

Pull every account into one place

To fix what the built-in tools leave behind, the trick is to stop working account by account and bring everything together at once. Export each account to a file — vCard (.vcf) or CSV (.csv) — and you have every copy of everyone in one small pile ready to merge:

• iCloud. Sign in at icloud.com, open Contacts, select all (Ctrl/Cmd + A), and use the gear menu's Export vCard…. You get one .vcf holding every card.
• Google Contacts. At contacts.google.com choose Export, then pick vCard or Google CSV — ContactAttic reads both — and save the file.
• Outlook / Microsoft. Outlook exports contacts to CSV natively via File → Open & Export → Import/Export → Export to a file → Comma Separated Values.

Do this for each account you set up on the new phone, plus any old backup you still have. Don't worry about the overlap between them — the overlap is exactly what the merge step is for. When you're done you'll have a small set of .vcf and .csv files that, between them, contain every copy of everyone the phone switch scattered — which is precisely the raw material a proper merge needs to rebuild one complete card per person.