American Railcar Industries is an American manufacturer and maintainer of hopper and tanker railcars, headquartered in Saint Charles, Missouri. Through its subsidiary American Railcar Leasing (ARL) it also leases railcars in the covered hopper and specialized tank car markets. As of 2013, investor Carl Icahn owns a controlling interest in both companies.

ARI was formed in 1994 as a subsidiary of ACF Industries (ACF), which had been leasing railcars since 1923. At that time ARI manufactured components for railcars, and also provided painting, repair and fleet management services. By 1999, the company was manufacturing both hopper and tanker cars.

In 2004 ARI formed a subsidiary company, American Railcar Leasing. This new company in turn acquired, via a series of transfer transactions between the related companies, the railcars and related leases from ACF Industries.

In 2006, ARI expanded by purchasing Custom Steel, a railcar parts manufacturer which had been owned by Steel industries.

In 2009, the company reincorporated in North Dakota to take advantage of the North Dakota Publicly Traded Corporations Act.

In 2014, ARL owns over 25,000 tank and covered hopper cars (with their two most common reporting marks being ACFX and SHPX) and serves the petroleum, chemical, food, agriculture, fertilizer and plastic pellet markets. In 2006 this totalled more than 10% of the lease cars in the United States.

The tank cars are used for a variety of liquid and liquified gas commodities such as vegetable oils, asphalt, various chemicals, LPGs and petroleum products. ARL's covered hopper cars are used for transporting commodities such as grains, plastic pellets, flour, sugar and various minerals.

ARL is headquartered in St. Charles, Missouri, a suburb of St. Louis, Missouri. They have five sales offices located in St. Charles, Missouri, Pointe-Claire, QC, Rochelle Park, NJ, Hinsdale, IL, and The Woodlands, TX.