Determining a mobile device’s locked or unlocked status is essential prior to changing service providers or traveling internationally. A locked phone is configured to function exclusively with a specific carrier’s network, while an unlocked phone can operate with any compatible network. For example, attempting to use a SIM card from a different carrier in a locked phone will typically result in a “SIM not supported” or similar error message.
The ability to ascertain this status offers numerous advantages. It allows consumers to ensure device compatibility with desired networks, potentially saving money on roaming charges when abroad, and increasing the resale value of the device. Historically, device locking was a common practice among carriers to recoup subsidized phone costs; however, unlocked devices offer greater flexibility and consumer choice.