A riverboat casino is a casino which operates on board a riverboat. Such casinos are found in several states in the United States with frontage on the Mississippi River and its tributaries, or along the Gulf Coast. In the 19th century, gambling on riverboats was a common but illegal practice. Several states legalized this type of casino in the early 1990s, in order to enable gambling while limiting the areas where casinos could be constructed. In some cases, the operation of the riverboat is a legal fiction, and the casino is permanently moored.
The legalization of riverboat casinos was in part a response to the federal Indian Gaming Regulatory Act of 1988, which allowed casinos to open on Native American reservations in much of the United States. States with few or no reservations sought to keep the tax revenues associated with gambling from going to states where Native American casinos were opening up.
The use of riverboat casinos has declined in the 21st century, as most states have permitted casinos to operate on land, increasing capacity and improving the safety of gambling structures – particularly after several floating casinos were destroyed by Hurricane Katrina in 2005. As of December 31, 2023, the American Gaming Association reports that there are 64 riverboat casinos operating in six states: Illinois, Indiana, Iowa, Louisiana, Mississippi, and Missouri. Missouri is the only state where all operating casinos are riverboats."State of the States 2024", American Gaming Association, 2024. Retrieved April 21, 2026.
History Paddlewheel riverboats had long been used on the Mississippi River and its tributaries to transport passengers and freight. After railroads largely superseded them, in the 20th century, they were more frequently used for entertainment excursions, sometimes for several hours, than for passage among riverfront towns. They were often a way for people to escape the heat of the town, as well as to enjoy live music and dancing. Gambling was also common on the riverboats, in card games and via slot machines.
When riverboat casinos were first approved in the late 20th century by the states, which generally prohibited gaming on land, these casinos were required to be located on ships that could sail away from the dock. In some areas, gambling was allowed only when the ship was sailing, as in the traditional excursions. They were approved in states with frontage along the Mississippi and its tributaries, including Illinois, Indiana, Louisiana, Mississippi and Missouri. Illinois also allowed limited riverboat casinos in the Chicago metropolitan area, which has a Mississippi River connection through the Chicago Sanitary and Ship Canal and the Des Plaines River, while Northwest Indiana has three 'riverboat' casinos in harbors along Lake Michigan.
An unusual situation occurred on the Potomac River in the mid-20th century due to a quirk in the state border between Maryland and Virginia. The border is not in the middle of the river, rather it is at the low water mark on the Virginia side such that the entire river is in Maryland, along with the District of Columbia's similar river border. As a result, there were several riverboat casinos docked off of the Virginia shoreline in the 1950s, when gambling was legal in parts of Maryland, but not Virginia. As the river was in Maryland, visitors could park in Virginia, and walk across a pier, crossing the state line in the process. There was no law in Maryland against having casinos on land, but this spared Virginia residents the trouble of having to cross the river, which could involve driving a significant distance out of the way to the nearest bridge.
As an example, in 1994, Missouri voters approved amending the state constitution to allow "games of chance" on the Mississippi and Missouri rivers. By 1998, "according to the state Gaming Commission, just three of the 16 operations comprising Missouri's $652-million riverboat gambling industry [were] clearly on the main river channel." The state supreme court had ruled that boats had to be "solely over and in contact with the surface" of the rivers. Several casinos had been on riverboats located in a moat or an area with water adjacent to a navigable waterway, leading them to be referred to as "boats in moats". The state legislatures were unwilling to give up the revenues generated by gambling. Over time, they allowed gaming casinos to be built on stilts, though with the requirement they had to be over navigable water.
Following Hurricane Katrina in 2005, which destroyed most riverboat casinos and their associated facilities of hotels, restaurants, etc., in states along the Gulf Coast, several states changed their enabling legislation or amended constitutions. They permitted such casinos to be built on land within certain geographic limits from a navigable waterway. Most of Mississippi's Gulf Coast riverboat casinos have been rebuilt on beachfronts with solid foundation systems since the hurricane.
Laws and history by state Illinois When Iowa legislators first proposed the legalization of riverboat gambling in the Quad Cities area in 1986, their counterparts in Illinois were concerned about the impact on the Illinois side of the Quad Cities, particularly on the Quad City Downs racetrack in East Moline.Dahlen, Ann. "Illinois Q-C legislators cool to riverboat gambling idea", Moline Dispatch, September 23, 1986, page 10. State legislators from the Moline area were split: Representative Bob DeJaegher led a push to pre-emptively ban riverboat casinos in Illinois, while Senator Denny Jacobs introduced a bill to legalize them. DeJaegher's proposed ban was passed on the same day in May 1987 that the Iowa House of Representatives voted to legalize the casinos."Lawmakers disagree on riverboat gambling", Rock Island Argus, May 6, 1987, front page and page A2. Neither measure was taken up in that state's senate before the end of their 1987 sessions, and neither state took action in 1988.Seitz, Patrick, and Diane Ross. "Iowa gives Illinois law mixed reviews; Riverboat gambling: a timeline of success; Governors discuss cooperation on gambling", Moline Dispatch, January 13, 1990, page A2.
After Iowa passed its legislation in April 1989, interest in Jacobs' bill was revived. Because House Speaker Mike Madigan and other Chicago-area leaders opposed the proposal, riverboat casinos were to be limited only to the Quad Cities, Peoria, and Rockford. To gain Republican support for the Democratic bill, Republican governor James R. Thompson suggested adding a provision that would freeze property taxes for the Arlington Park racetrack, still recovering from its 1985 fire. This compromise worked in the Senate, where it passed on June 30, 1989, but failed in the House the same day."Odds lengthen on riverboat gambling", Moline Dispatch, July 1, 1989, page A2. Despite efforts to revive the bill in October, it was not taken up in either chamber before the legislative session ended in November."Riverboat gambling sinks until next year", Associated Press, Galesburg Register-Mail, November 3, 1989, page D-5.
However, when the next legislative session began in January 1990, the Jacobs bill was quickly brought back. On January 11, it came up for a vote in both chambers. In the House, the Riverboat Gambling Act passed by one vote, after Richard Mautino changed his vote mid-tally. The bill passed the Senate nine minutes later by two votes.Burrows, Kenda, and Diane Ross. "Riverboat gambling passes by one vote", Moline Dispatch, January 12, 1990, page A6. Governor Thompson signed the bill on February 7,Ross, Diane. "Ramifications of riverboat gambling bill are explained", Rock Island Argus, February 11, 1990, page B6. thanking the legislature "for helping me beat Iowa" (since Illinois' law would go into effect three months earlier than Iowa's).
The law established the Illinois Gaming Board. It allowed riverboat casino operations on the Mississippi River, and on the Illinois River south of Marshall County, to begin January 1, 1991, and on all other navigable waters of the state except Lake Michigan and any part of Cook County on March 1, 1992. The Board was empowered to issue five licenses in 1991, four on the Mississippi and one on the Illinois, and another five in 1992. Gambling would not be allowed while the boats were docked. Legislators had promised to set a maximum loss per person per casino visit of $500, but this provision was left out of the law as passed. This was initially said to be a mistake that would be fixed by the passage of a "cleanup bill", but the fix was never passed.Ross, Diane. "No lid for boat gaming", Southtown Star, June 10, 1990, page A-6.
While riverboat gambling was technically legal in Illinois before Iowa, no casinos were licensed in Illinois before Iowa's opened on April 1, 1991. The first riverboat casino in Illinois, the Alton Belle, began operating on September 10, 1991."Riverboat gambling floats in Alton", United Press International, via the Moline Dispatch, September 11, 1991, page A7. The Illinois Gaming Act of 1999 modified the law to allow gambling to take place on permanently moored barges, responding to previous similar changes in Iowa."Public Act 91-0040", State of Illinois, 91st General Assembly, June 1999. Retrieved April 25, 2026.Patterson, John C. "Gambling plan moves to Illinois Senate", Decatur Herald and Review, May 24, 1999, page A14.
Beginning in 2009, Illinois has allowed bars and taverns to operate Video Gaming Terminals, low-stakes slot machines, in thousands of locations across the state. This led to a reduction in revenue at the state's riverboat casinos."State of the States 2018", American Gaming Association, 2019. Retrieved April 25, 2026. Subsequently, the state passed gaming expansion legislation in 2019, allowing casinos to operate on land for the first time and expanding the total number of statewide casino licenses from 10 (where it had been since 1992) to 16. As of December 31, 2024, six casinos in Illinois still operate as riverboats or moored barges although it is no longer required."State of the States 2025", American Gaming Association, 2025. Retrieved April 25, 2026.
Indiana
Riverboat gambling was legalized in Indiana in 1993, with a maximum of 11 casino permits to be made available by the state: five on Lake Michigan, five along the Ohio River, and one in Patoka Lake. The first riverboat casino in Indiana was the Casino Aztar Evansville, which opened in 1995. In 2015, the legislature amended the casino law to allow the state's riverboat casinos to move into land-based facilities on their existing sites, to help them remain competitive with casinos in neighboring states. As of December 31, 2024, six casinos in Indiana still operate as riverboats or moored barges, while another five casinos have relocated to land-based structures.
Iowa Iowa was the first state to move to legalize modern riverboat casinos, passing a bill to do so in 1989. This was in part a response to the passage of the federal Indian Gaming Regulatory Act of 1988, which allowed casinos to open on Native American reservations in neighboring Minnesota and Wisconsin. Since Iowans would be traveling to new nearby casinos to gamble no matter what the state did, legalizing riverboat casinos would keep the associated tax revenues in the state, bolster the depressed economies of the cities where the boats docked, and revive a mythologized part of the region's past.Nelson, Michael. How the South Joined the Gambling Nation: The Politics of State Policy Innovation, Louisiana State University Press, 2007.