Post-contract support (PCS) refers to the ongoing technical support software companies provide customers after an initial contract is signed. Support is typically offered via multiple channels, including web, email, phone, and video conference. With traditional perpetual software licenses, customers are charged an annual maintenance fee that includes both support and access to product upgrades for 15-20% of the license cost. In modern subscription models, a base level of support is bundled into the service. Some software providers offer a premium customer support model for an additional fee.