How to back up your contacts before switching phones

By Michael, founder of ContactAttic · September 2026 · 7 min read

A phone switch is exactly when contacts quietly go missing. The setup wizard says "transfer complete," but months later you notice the plumber's number is gone, your cousin shows up as three half-filled entries, and the coworker you only ever texted from the old SIM has vanished entirely. The transfer isn't malicious — it just doesn't back up what it doesn't see. Do a real export first, and the switch stops being a gamble.

Why contacts get lost or duplicated in a switch

Your contacts don't live in one tidy place to begin with — they're split across the SIM card, the old phone's local storage, whichever cloud account you're signed into, and any app that keeps its own address book. A phone switch touches all of those at once, unevenly:

• Account sync migrates some of it. Signing into Google or iCloud on the new phone pulls down whatever that account has stored — but only what it has stored.
• SIM-only contacts get left behind. Numbers saved to the SIM card, common on older phones, aren't part of any account. If nobody explicitly imports them, they don't travel.
• App-only contacts get left behind too. WhatsApp, a work chat app, or a CRM can hold contact cards that never synced to your phone's main address book, so a "transfer your contacts" step never sees them.
• The same person ends up as three half-filled entries. The SIM copy has just a number, the account copy has a name and email, an app copy has a different number again — and now you have three incomplete cards instead of one complete one.

None of this shows up until you go looking for someone and they're not there, or you find them three times with three different phone numbers and no way to tell which one is current. A backup taken before the switch, rather than trusting the migration to catch everything, is the only way to be sure nothing depended on a single device that's about to be wiped or handed off.

Export a real backup, per platform

An account sync is not a backup — it's a live connection that can miss things and that you don't control. A backup is a file, saved somewhere that isn't the phone. Both iPhone and Android will export your contacts as vCard or CSV in a couple of minutes:

• iPhone. Sign in at icloud.com, open Contacts, select all (click one, then Ctrl/Cmd + A), and use the gear menu's Export vCard…. Full walkthrough, including a Mac-based route: how to export your contacts from an iPhone.
• Android. Open the Contacts app or contacts.google.com and export to vCard or Google CSV. Full walkthrough, including how to catch SIM-only entries: how to export your contacts from an Android phone.

The part people skip is what to do with the file afterward: save it off the phone. A .vcf or .csv sitting in the old phone's downloads folder is no safer than the contacts app it came from — if that phone gets wiped, traded in, or lost before you double-check the new one, the backup goes with it. Copy the file to your computer, and keep a second copy somewhere separate — a different drive, a cloud folder, wherever you'd put anything else you can't afford to lose. Two copies in two places is what makes it an actual backup rather than a temporary file.

Turn the export into a durable master copy

A single export is a snapshot of one account at one moment — useful, but if you've ever added a second account, imported an old SIM, or let an app write its own cards, that snapshot is missing pieces or carrying duplicates of its own. The next step is to fold every export you have — this phone's, any old phone's, any account's — into one file that's actually complete:

1. Gather every export. The .vcf from your iPhone or Android backup, plus any older exports or CSV files you're still holding onto from a previous switch.
2. Merge and de-duplicate. Match entries across name, phone, and email so the same person's SIM card, account copy, and app copy collapse into a single complete entry instead of three partial ones — union-find matching, not a simple exact-name match that misses everything spelled slightly differently. See how to merge duplicate contacts into one clean address book and how to clean up contacts after switching phones for the full process.
3. Keep the clean file locally, on your own computer. Once you have one de-duplicated contacts.vcf, the next phone switch stops being an export-and-hope exercise — it's a straight import of a file you already know is complete.

ContactAttic is built for exactly this step: point it at your exported .vcf and .csv files and it merges every copy of every person into one card, keeping the phone numbers and emails and dates from each, and writes a clean file plus a report of what was combined. It's one of five local-only apps in the Attic family, each built around the same idea: your personal data gets organized on your own computer, not handed to someone else's server.

Frequently asked

How do I transfer contacts to a new phone?

Signing into the same Google or iCloud account on the new phone brings across whatever that account has stored, which covers most people most of the time. But SIM-only and app-only contacts won't come along that way, so export a full vCard or CSV backup first — see the platform guides above — and you have a fallback if the sync misses anything.

Where are my contacts backed up?

By default, wherever your phone's account syncs to — a Google or iCloud account, typically — which is a live connection, not a file you control. A real backup is a .vcf or .csv file you've exported and saved somewhere off the phone, such as your computer, so it still exists even if the account or the device itself has a problem.

How do I export all my contacts?

On iPhone, sign in at icloud.com and use Export vCard… from Contacts. On Android, export from the Contacts app or contacts.google.com. Both give you a single file holding every card, which you can then save to your computer as a real backup.

Will I lose contacts if I don't back them up first?

Possibly, and often silently. Account sync only moves what's in that account, so SIM-only numbers, app-only contacts, and anything saved locally to the old phone can be left behind with no warning that they didn't come across. Exporting a backup before you switch is what catches those before the old phone is wiped or handed off.