Changing Your Number Is More Work Than You Expect
People change their phone number for all sorts of reasons: relentless nuisance calls, being stalked, or simply taking the opportunity when switching handsets. Changing the number itself is easy enough at a mobile phone shop - it is everything that comes afterwards, telling people, that turns out to be the hard part.
A phone number functions as a kind of identity document attached to your smartphone. Banks, social media, online shopping, two-factor authentication - many of the services you use are tied to your phone number. Changing that number means working through each of those registrations one by one. Change it without preparing first and, in the worst case, you can find yourself locked out of your banking app or unable to get into your social media accounts.
The People to Tell First
Family and close friends
Start by giving your new number to family and close friends. LINE or email works for most of them, but for grandparents and others who do not use LINE you will need to call and tell them directly.
School and workplace
Ask your school's emergency contact list or your workplace records to be updated with the new number. These lists are also used to check that people are safe during a disaster, so updating them early matters.
Services That Use SMS Verification (Most Important of All)
A particularly common source of trouble when you change your number is services that use SMS verification for two-factor authentication. Once the text messages stop arriving at your old number, you may find you can no longer log in at all.
- Google account: in your account security settings, replace the number used for two-step verification
- Apple ID: in your Apple ID settings, change the number you sign in with
- LINE: change the number in the app settings, and do it while text messages still reach your old number
- Banking apps: change it in each bank's app or at a branch. It also affects authentication for online banking
- Amazon: in your account settings, change the number used for signing in
- Payment apps such as PayPay and Rakuten Pay: change it in each app's settings
If you can, switch your verification method from SMS to an authenticator app such as Google Authenticator before you change your number - then the change has no effect on you at all.
Social Media and Messaging Apps
Instagram, X (formerly Twitter), TikTok and Discord may all have asked for a phone number when you signed up. In most cases you can change the registered number from the account details screen inside the app settings. The names and positions of those menus can change with app updates, so look for whatever plays the role of "Account" in the settings screen. If you use the number for two-factor authentication, check those settings as well.
Public Bodies and Contract Providers
- Banks and credit card companies: change it at a branch or in the app. If you changed your number without using number portability, be sure to notify them
- Insurance companies: your policyholder details need updating
- Hospitals and your regular doctor: your number may be on file as an emergency contact
- Your municipal office: the contact number you have registered for local government procedures
- Electricity, gas and water: your phone number is registered against the account
- Your letting agent or landlord: the contact number on your tenancy agreement
The Services People Forget
These are easy to overlook, yet they very often have your phone number on record.
- Delivery company membership services: the Yamato Transport, Sagawa Express and Japan Post apps
- Loyalty cards: shared schemes such as Ponta and Rakuten Point
- Subscriptions: Netflix, Spotify, YouTube Premium and so on
- Marketplace apps: Mercari, Rakuma and similar
- Booking sites: Hot Pepper, Tabelog, Jalan and others
- Anything car-related: car insurance, JAF roadside assistance, your dealer's contact record
What to Do Before You Change the Number
- List every service that uses SMS verification
- If possible, switch those services to email or an authenticator app before the change
- While you can still receive messages at the old number, finish updating the number on your important services
- Go through your phone's contacts app and list the people who have your number saved
- Search your email inbox to uncover services that have sent you phone number confirmation messages
Ways to Avoid Changing Your Number at All
If nuisance calls are the reason you are considering a new number, there are ways to deal with the problem without changing it.
- Call blocking: block specific numbers using your phone's settings or a service from your carrier
- Nuisance call filtering: subscribe to the nuisance call countermeasure service your carrier offers
- Adding a SIM card: get a second number as an eSIM and keep it separate from your private one
- Number portability: if all you want is a different carrier, portability lets you keep your number. There is no need to change it
Changing your number is a lot of work, so try these approaches first. Call blocking in particular needs nothing beyond your phone's built-in features: on an iPhone you can block a caller straight from the call history, and on Android you can block a number from the call log menu, though the wording differs between handsets.
Your Old Number Gets Reissued to Someone Else
Once a phone number is cancelled, it is assigned to a different person after a set interval - this is number recycling. If you forget to update a service that is tied to your old number, its text messages may end up reaching the new owner. Two-factor authentication codes arriving in a stranger's hands is a serious security risk.
If you use number portability to switch carriers, your number does not change and this concern does not arise. Rather than changing the number, consider changing only the carrier and keeping the number through portability.
Summary
The key to changing your number is the preparation you do beforehand. List every service that uses SMS verification and move them over while the old number still works. After the change, go through family, friends, school and every service provider so that nobody is left out. Writing a checklist and crossing off one item at a time is the surest way through it.
Changing a number takes more effort than most people imagine. Putting it off because it feels like a chore risks locking you out of services you cannot afford to lose. Banking and payment apps deserve special attention: forgetting to update the number there can turn into trouble involving your money. Use the checklists in this article and work through the change to a plan.