After that, you can unlock it and use it with the carrier of your choice. Since you’ve signed a contract with that specific carrier, you’ll have to stick with them until the contract is up or the payment plan gets paid in full. If you bought your phone through a carrier, either on a two-year contract or a monthly payment plan, your phone is locked to that service provider, even if it is compatible with other networks. It’s safer to buy an unlocked device directly from the manufacturer, but you can find these cross-compatible cell phones at a lower price on eBay and other third-party seller sites. Your carrier can unlock your phone for you once specific criteria get met, or you can purchase an unlocked device. Older phones were not always compatible with other carriers because they featured carrier-specific attributes. Until that phone gets paid off, it will remain locked to that company’s network. Most carriers will sell you a device on an installment or leasing program. While it certainly made sense that a carrier would want to lock down the features of their specific models, it made reselling or refurbishing smartphones a complicated process for anyone who wasn’t a high-level tech genius, resulting in tons of smartphone waste. Until then, you’re stuck with the original network provider. Once unlocked, the phone is yours to use as you please. If you’d like to use another carrier’s SIM card in your cell phone, you can verify it is unlocked.