SIM library

SIM library: keeping a prepaid number alive

How 9 carriers in 5 markets decide when an unused number is lost, what keeping it costs, and the day we last read each carrier's own page.

United States

3 carriers

Mint MobileA US prepaid carrier selling 3-, 6- and 12-month plans. A lapsed term suspends the line, and after 60 days Mint may reassign the number.4 plans · From USD 180 a year
Helium MobileA US carrier with two paid plans, Air and Infinity. Its free Zero plan ended on 11 June 2026, so keeping a number there now costs money every month.2 plans · From USD 180 a year
TelloA US prepaid carrier where you build the plan from minutes, texts and data, from 5 dollars a month. Keep a monthly plan active to hold the number.1 plan · From USD 60 a year

Hong Kong & Macau

2 carriers

Mainland China

2 carriers

Japan

1 carrier

povo 2.0A Japanese online plan with a 0-yen base. To keep the number you must buy a paid topping within every 180 days, or povo suspends the line.

Taiwan

1 carrier

Chunghwa Telecom Prepaid CardA Taiwan prepaid number valid for 180 days from the day it was set up. Each top-up restarts the 180 days, up to a balance cap of NT$5,000.

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Compiled from each carrier's public pages and checked on the date shown. Rules and prices change without notice, and the carrier's current terms always prevail. General information only, not advice.

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