reverse the charges
Etymology
English
This phrase comes from the early days of the telephone system in the late 1800s, when an operator would manually 'reverse' the billing — changing who was charged for a call from the caller to the receiver. The verb 'reverse' here means 'to turn or change to the opposite direction or position,' and 'charges' refers to the cost of the telephone service. The expression became fixed in British English telephone terminology and remains the standard term in the UK, Australia, and other Commonwealth countries.