What is Subsidy Password?

A subsidy password, also known as an unlock code, is a code that is required to unlock a mobile phone from a specific carrier. When a mobile phone is purchased from a carrier, it is often sold at a discounted price with the expectation that the customer will remain loyal to the carrier for a set period of time. To ensure this, the carrier will lock the phone to their network, meaning it can only be used with their SIM card.