FO是一种装卸条款，具体见下文。

Free In (FI) in the international ocean freight terminology the word “Free” means “Not included”. I.e. if FI, then the shipper is responsible for the coast of loading goods onto a vessel for the international shipping overseas.

Free Out (FO) is the international shipping term in ocean freight that indicates that the consignee (recipient) is responsible for the cost of unloading cargo from the vessel at the destination.

Free In and Out (FIO) is the international shipping term used in the ocean freight industry means that the carrier is NOT responsible for the cost of loading and unloading gods onto/from the vessel.

从上述描述可以看出，FO指的是船方不承担卸货费用，应由收货方承担；FI指的是船方不承担装货费用，应由发货方承担；FIO指的是船方不承担装货和卸货费用。

来源：

https://www.kkfreight.com/free-in-free-out.html