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Phone Number Basics

What to Do When You Change Your Phone Number - A Checklist to Avoid Missing Contacts

About 2 min read

Changing Your Number Is More Work Than You Think

The number change itself is easy at the carrier shop, but notifying everyone afterward is the hard part.

Priority Notifications

Family and close friends first, then school/workplace. Update SMS-authenticated services (Google, Apple ID, LINE, banks) before changing - or you may get locked out.

Before You Change

List all services using SMS authentication. Switch to email or app-based authentication where possible. Complete critical service updates while you can still receive SMS on the old number.

Your Old Number Gets Recycled

Cancelled numbers are reassigned to new users. Any services still linked to your old number may send SMS to a stranger.

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Frequently Asked Questions

What happens to my LINE account when I change numbers?

You need to update your number in LINE settings before losing access to the old number. Go to LINE Settings > Account > Phone Number to register your new number.

How much does it cost to change your number?

Typically 2,200-3,300 yen depending on the carrier. Some carriers allow online processing.

Can I stop nuisance calls without changing my number?

Yes. Use your phone's call blocking feature or your carrier's nuisance call filter service. You can also get a second number via eSIM and use it for personal contacts.

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