A boxcar (the American term; the British call this kind of car a "goods van") is a railroad car that is enclosed and generally used to hold freight. The boxcar, while not the simplest freightcar design, is probably the most general-purpose, since it can carry most loads. Boxcars have side doors of varying size and some have end doors to load very large items.

Boxcars can carry most kinds of freight. Originally they were hand-loaded, but in more recent years mechanical assistance such as forklift trucks have been used to load and empty them faster. Their generalised design is still slower to load and unload than specialised designs of car, and this partially explains the decline in boxcar numbers since World War II. The other cause for this decline is the container. A container can be easily transshipped and is amenable to intermodal transportation, carryable by ships, trucks or trains, and can be delivered door-to-door. In many respects a container is a boxcar without the wheels and underframe.

Even loose loads such as coal and ore can be carried in a boxcar, with boards over the side door openings. This was more common in earlier days; it was susceptible to losing much loading during the journey, and damaged the boxcar. It was also impossible to mechanically load and unload.

Livestock can be carried in a boxcar, but there is insufficient ventilation in warm weather. Specially built or converted stock cars are preferable.

Historically automobiles were carried in boxcars, but during the 1960s specially built auto carriers took over; these carried more cars in the same space and were easier to load and unload. The automotive parts business, however, has always been a big user of the boxcar, and larger capacity cars evolved in the 1960s to meet the auto parts industry's needs.

In recent years hicube boxcars - high cubic capacity - have become more common. These are higher than regular boxcars and can only run on routes with increased clearance.

While not holding the dominant position in the world of railborne freight that they had before World War II, the boxcar still exists and is used in great numbers around the world.

Passenger and Wartime Use

The boxcar has been known to carry passengers, especially during war time. In both World Wars, French boxcars known as forty-and-eights were used as troop transports as well as for freight; in World War II by first the French, then the German occupiers, and finally the Allied liberators. In addition to soldiers, the Nazis infamously transported prisoners in overcrowded boxcars. The United States used troop sleepers to ferry U.S. soldiers through North America during World War 2, which were both based upon boxcars and intended to be converted into boxcars after the war was over.

Hobos and migrant workers have often used boxcars in their journeys, since they are enclosed and therefore they cannot be seen by railroad-employed security men ('Bulls') or police, as well as being to some degree insulated from cold weather.