- For a listing of cargo types, see the Cargo category
In OpenTTD, Cargo is what you, as a transport company, transport (relocate) between cargo agents. Cargos are produced by some cargo agents, like industries and towns, and they are accepted (consumed) by other agents as well.
All accessible cargo exist in the form of discrete, atomic units of the fixed physical quantity/size. E.g. a single transportable unit of oil always consists of 1000 litres exactly. All productions, transfers and consumptions are conducted atomically with the cargo units.
Cargo can only be accessed at an agent via a station. Industries and town-buildings that are within a station's catchment area accept (consume) cargo and passengers through this station, and will place (produce) their cargo at the station to be transferred elsewhere. (In some industries, only certain squares can accept cargo. See catchment area for more information.)
A production process creates new cargo units and places (delivers) them to nearby stations, if available. A consumption/acceptance process effectively destroys cargo units in the stations upon unloading and pays for their transportation service. Some agents are able to produce and accept cargo at the same time; in some cases the agent produces and accepts the same type of cargo - unloading that type permanently destroys all old units (standart payment occurs), unless the vehicle is ordered to transfer.
A production agent checks certain conditions before delivering the cargo to a station. This is a crucial (and somewhat obscure) part of a competetive play. It involves companies competition, logistics, service throughput effectiveness and local reputation (rating). Refer to delivery and game mechanics.
Once cargo unit is delivered to a station, the station's owner company effectively controls it. From this moment the company alone decides where or how to transfer or store it. The company can't sell the cargo however. The only way to get any profit from those possessed cargo units is to unload them at a station with accepting agent nearby. Each cargo unit tracks its own age, starting from the moment it was produced; some cargo types deteriorate faster than others and must be served faster. The transfer costs always include age penalty. Cargo dissipates/vanishes over time at stations if stayed for too long. Companies are not directly charged for those losses.
Passengers and Mail are also types of cargo, mainly produced and accepted by towns. Different building squares in towns accept differing amounts of passengers and other cargo. The acceptances can be found out by using the land area information tool (question mark). If a square can't accept a cargo by itself, the amount is noted by 1/8's. There has to be at least 8/8 of a cargo type in a station's catchment area for the station to accept that cargo.
Some industry tiles also accept 1/8 of passengers. Industries however, except for Oil Rigs, don't produce any passengers. Most notably, Steel Mills have many 1/8 squares and can accept passengers on their own. Furthermore, the Company Headquarters accepts and generates some passengers and mail to help players in the very beginning of the game.
See cargo income for more information on how income is calculated.
Below are charts and tables showing each Cargo in each climate, and what produces and accepts them.