Before you change your phone number or stop using your old one, move your bank, payment and social accounts to the new number first, and don't just let the old one run up unpaid bills until it is cut off

Cost

Free. You have to go account by account to change the linked number, and the number your bank has on file must be changed through the bank. If you have many frequently used accounts, it can take one to two hours in all. The hard part is that it is easy to miss accounts, and you can't remember the rarely used ones.

What you get

The telecom service regulations state that "the freeze period for a mobile phone number is at least 90 days," meaning the time from a number's cancellation until it is put back into use. Once 90 days have passed after cancellation, the number may be issued to a new user. In its notice on telecom service quality for the first quarter of 2025, the Ministry of Industry and Information Technology (工信部) reminded users that they can use the "secondary number refresh" (二次号码焕新) service in the apps of the three carriers. If you get a number someone else has used, it lets you unlink the internet accounts that were registered and linked to this number before you opened your line. The notice for the second quarter of 2026 says the service now covers 258 commonly used internet apps, with more than 850,000,000 (8.5亿) requests to unlink apps. That new number owners make a special effort to unlink shows that the previous owner's accounts were still linked to the number when it reached them. In 2024 the customer service of the three major carriers was interviewed by People's Posts and Telecommunications News (人民邮电报). They said that after a number is canceled, a new user can still use a text-message code to log in to an account registered by the old user. They reminded users to unlink apps such as Alipay and WeChat before changing or canceling a number, and to promptly change the phone number their bank has on file for their bank cards (China)

Notes

First use the One-ID Check 2.0 (一证通查 2.0) to see how many accounts the old number is linked to; see §14.11 (how many phone numbers are in your name). Change your bank and payment accounts first, then your social accounts, and cancel accounts you no longer use outright. Don't shut off the old number right after changing; keep it for a month or two to catch verification texts you missed. This is the author's own experience. That a new number owner can log in with a verification code comes from what carrier customer service said in media reports, not from an official notice or a court ruling. For what to do once someone has logged in to your account, see §14.6 (login devices). When you change phones or sell an old one, you also need to log out of accounts and restore factory settings; this is covered in the note of §14.8 (deleting your own personal information). Rated C because no study has worked out how much loss re-linking prevents. The size of the benefit is set at medium by judgment. The beneficiary is you.

Evidence grade

C : The author's experience or common practice, without direct literature.

Sources

1. 信息产业部 (2005). 电信服务规范（信息产业部令第 36 号，附录 2 第 2.1.7 项）. https://www.miit.gov.cn/zwgk/zcwj/flfg/art/2020/art_0cff75e226764dc7b811cd4e954415c5.html
2. 工业和信息化部 (2025). 关于 2025 年第一季度电信服务质量的通告（工信部信管函〔2025〕85 号）. https://www.miit.gov.cn/jgsj/xgj/fwjd/art/2025/art_1bcadc32bf8141a8b616db8eaadba2e9.html
3. 工业和信息化部 (2026). 关于 2026 年第二季度电信服务质量的通告（工信部信管函〔2026〕258 号）. 内蒙古自治区通信管理局转载. https://nmca.miit.gov.cn/xwdt/xydt/art/2026/art_2f6af9120a064a6784557cdefbf1c5be.html
4. 李玥 (2024). 三大运营商提醒用户：变更或注销手机号码前务必先解绑. 人民邮电报，西藏自治区党委网信办转载，2024-04-08. https://wxb.xzdw.gov.cn/wlaq/aqdt/202404/t20240408_456634.html（网页存档 https://web.archive.org/web/20250414055537/https://wxb.xzdw.gov.cn/wlaq/aqdt/202404/t20240408_456634.html）

Translated from the Chinese original. Original book, section 14, tip 12. Content may be out of date and rules differ by place. When you actually deal with an agency, a doctor or a court, follow what local officials, doctors and lawyers tell you. Disclaimer