A transit transfer is proof of payment allowing riders to switch between vehicles or routes within a specified time period without paying additional fare. Transfers facilitate trips requiring multiple buses or routes to reach destinations. Traditional paper transfers are being replaced by electronic systems where fare cards or smartphone apps automatically recognize valid transfers. Transfer policies specify validity periods, eligible connections, and any restrictions. Transfers are fundamental to transit systems where no single route serves all destinations. Free transfers within limited time windows encourage transit use by making multi-route trips affordable. Transfer policies affect rider convenience and system revenue. Integration between different transit systems (bus, train, regional services) may require transfer agreements between operators.