Free Time refers to the period during which an import/export container can be stored at a port free of charge. This is a negotiated time between the carrier and the shipper, during which the customer who receives and delivers the container can store it at the port free of charge for a certain period of time without additional fees. Typically, free time is provided for a certain number of days (e.g. 7 days, 10 days, etc.), and after that, demurrage charges will be incurred.
Source : ChatGPT