Sports betting is everywhere now. Advertisements for betting apps starring famous athletes play during game broadcasts and on social media. Commentators discuss betting odds live on air. The National Basketball Association’s streaming app League Pass allows fans to place live bets while watching a basketball game.

This explosion has followed a 2018 U.S. Supreme Court ruling that struck down a law that had prohibited most states from legalizing sports betting. So far 30 states and Washington, D.C., have legalized online betting on sports, and the nascent U.S. industry is worth $10 billion and growing. According to a 2024 survey, one in five people have an account with an online sports betting service, and most of those people use a betting app on their smartphone.

These mobile apps have made sports betting quicker and more accessible than ever. They have also granted companies access to troves of data on their customers’ behaviors, which they can use to keep people betting—making it easier than ever to fall into problematic behaviors, experts say, and harder than ever to quit.

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“The features that make these products exciting and engaging are also the features that make them addictive,” says Heather Wardle, a policy researcher studying gambling at the University of Glasgow.

Getting Hooked

Gambling in any form can be addictive. The thrill of a win activates the brain’s reward system in a way that can warp someone’s perception of risk. There are three phases to developing a gambling problem, explains Lia Nower, who leads the Center for Gambling Studies at Rutgers University. First, a person starts to overemphasize their wins, leading them to gamble more. As they play more, they will inevitably enter the losing phase and may begin “chasing losses”—gambling more in the hopes of recouping those lost funds. This then causes a downward spiral into desperation and hopelessness, which can lead to financial or even physical harm for the person and those around them.

Like addiction to substances such as alcohol or opioids, gambling addiction is considered a mental health disorder. But a gambling problem doesn’t have to reach this level of severity before it can cause harm. Research from the past decade has shown that “the harms are much wider and much more broadly distributed than previously assumed,” Wardle says. Gambling can impact entire families and communities. It increases the risk of suicide and domestic violence. Perhaps most devastatingly, gambling problems are most common among people who have the least money to lose.

Researchers are already observing financial harms as states have legalized online sports betting. In a recent working paper that was posted to the repository SSRN and has not yet been peer-reviewed, researchers found that four years after a state legalizes online sports betting, consumers’ average credit score drops by an average of 1 percent, and the likelihood of filing for bankruptcy increases by 25 to 30 percent.

Dark Patterns

Not all forms of gambling carry the same levels of risk. Engaging in a game of poker with friends, for example, is less dangerous than playing a slot machine. Slots have long been casinos’ greatest moneymaker because of their addictive potential. Jamie Torrance, a psychologist studying gambling at Swansea University in Wales, chalks this up to the machines’ incredible pace—unlike in a game of poker or blackjack, only seconds pass between placing a bet and winning or losing. This makes the experience more immersive, leading some slot players to enter a trancelike state called “dark flow” in which they become completely absorbed by the game, Torrance says. The fast turnarounds can closely link the act of pressing the button with the rush of dopamine of a potential win, conditioning a person to keep pulling the lever.

Sports betting was once a slow form of gambling, with people mainly betting on the outcome of a game or race in person or with a phone call. With digital apps, people can bet 24/7 and are also now putting money on smaller events, such as which team will score first or whether someone will miss a free throw. And they can string these micro bets together into one big bet called a parlay—a popular feature that has big potential winnings but usually doesn’t pay off.

Sports betting is “becoming far more rapid,” Torrance says. “It’s not as harmful as a slot machine, but it’s moving in that direction.”

Still, these apps can do something that slot machines, or even the bookies and casinos of old, can’t: track users’ betting activity in incredible detail. Sports betting outlets, or sportsbooks, are able to use information about how and when someone bets and what that person bets on to determine what offers they send, Wardle says. To her, this consumer profiling is one of the more concerning aspects of these online gambling products.

“Imagine what the tobacco companies would have done if they had known every single time you took a cigarette out of a pack—if they’d have known exactly how much you smoked, when you smoked, how often you smoked, the circumstances around your smoking,” she says.

Wardle recently co-led a commission on gambling’s risks to public health. In their report, published in October in the Lancet, she and her colleagues referred to some of these apps’ features as “dark patterns,” a term used in product design for a user interface that exploits cognitive biases to get people to act outside of their best interest. A 2022 audit of 10 online gambling apps available in the U.K. identified common deceptive marketing and design practices that could cause harm, including:

• A sign-up process that is frictionless and often lacks effective age verification

• Deposit or bets with a default amount that is higher than the actual minimum amount, which leads people to choose the higher amount because of a principle called “anchoring”

• Deposits and bets that can be placed with one click

• Safety tools that are hard to find

• A minimum account balance that is required to withdraw money

• Prompts to place another bet that appear immediately after a previous one

• The absence of a feature that displays how much a user is losing during gameplay

• Push notifications and e-mails that stress the urgency and scarcity of betting offers

• Accounts that are hard to close or “immortal” (meaning they can never be fully closed)

These kinds of features encourage customers to spend more time and money betting, Torrance says. The gambling companies, he says, “have all of this knowledge about how the human mind works, how human behavior works, and they essentially use that knowledge for profits.”

And some of these features can make it challenging for people with gambling problems to quit in the first place, let alone to stay away. A lapsed customer who receives a push notification, e-mail or text with an enticing “limited time” offer for 10 “free bets” might be someone with a gambling problem who is trying to quit.

Imagine someone with alcohol use disorder who has been sober for two weeks, Torrance says. “They’re on their way to work, and the person who works in their favorite pub or bar comes out and says, ‘I have a free shot of tequila; please have it….’ It’s going to be very hard for that person to deny that.”

Who’s Responsible?

Joe Maloney of the American Gaming Association, a trade group that represents the U.S. legal gambling industry, says that sportsbooks use these features in part because they “exist in a competitive marketplace.” Sportsbook operators are competing not only with other with their peers but also with illegal gambling operators that offer “slick” and “innovative” user experiences, he says. “To the extent you continue to introduce friction into the legal, regulated gaming experience, you are potentially risking losing that customer.”

Customers have also come to expect personalized prompts and frictionless experiences in their digital lives, and gambling apps are no different, Maloney says. People “don’t want to be served the Australian Open right now [if they’re] not interested in tennis,” he says. “It is about meeting the consumer where they are.” He also stresses that the apps should be thought of as entertainment and not a way to generate wealth.

When asked about whether the same design and marketing strategies should be used for an addictive product such as gambling, Maloney points to the apps’ many safety features, which are required by law in some states. Customers can choose to limit the amount of time and money they can spend or even to voluntarily ban themselves from the app.

In her research, Nower has found that bettors infrequently use these safeguards. She and her colleagues analyze every sports bet placed in New Jersey each year to create reports for the state’s gambling regulators. They have found that across years, only around 1 to 4 percent of people under age 25 use any of the safety features, she says.

The gambling industry stresses the importance of playing responsibly. But Nower, Torrance and Wardle each criticize that industry for putting all of the responsibility on individuals. “It’s very simple to say, ‘It’s all about individual responsibility,’” Wardle says. “It’s very good for the industry to do that because it then absolves them from the corporate responsibility that they bear” as the ones designing, promoting and providing their products.

Gambling is also becoming more popular among young people, who are more vulnerable to addiction. In a survey conducted from December 2020 to May 2021, Nower and her colleagues found that among New Jerseyans who gambled, 33 percent of those aged 18 to 24 only gambled online, a proportion nearly five times higher than in 2017 and higher than in any other age group. And 19 percent of the 18-to-24-year-old group that gambled reported high-risk behavior and experiences that could be indicative of a gambling disorder.

Though the legal gambling age is 21 in most states—including New Jersey—it isn’t hard to get around age verification. A child or teenager might have access to the identification, credit cards or accounts of an adult, with or without their consent. “There’s no way to know if this person [placing a bet] is 50 or 15,” Nower says. There are also internationally registered sports betting sites that are available to people 18 and older in the U.S.

Children are also being exposed to gambling at younger ages through video games. “In many ways, gambling and video gaming are now indistinguishable,” Nower says, thanks to common features such as loot boxes and skin betting, a form of gambling in which virtual items are used as in-game currency. And popular “social sportsbook” apps can allow users to place sports bets with virtual currency without age verification. “It’s getting you used to losing money but continuing to play,” Torrance says. And “that feeling is going to cross over then when you’re actually playing with your own money.”

So far regulations on gambling ads in the U.S. have been spotty. Ohio has banned the marketing terms “free bets” and “risk-free,” and New York State recently passed a law requiring ads for gambling to warn consumers about its potentially dangerous effects. Other countries have widespread restrictions: the U.K. banned gambling advertisements featuring celebrities in 2022, and Italy banned gambling ads altogether in 2018.

Torrance advocates for regulations that would reduce the speed and ease of placing bets on mobile apps. Australia, for example, requires people to place bets over the phone once a game has already begun. Regulators could also impose a delay on bank deposits into gambling apps. Nower suggests that requiring people to opt out of safety features such as deposit limits rather than opt in could also reduce the risk of harm.

In the U.S., legal sports gambling is still in its infancy. Torrance hopes that the country can learn from the mistakes made in the U.K., where sports betting has long been legal and has “completely saturated” the world of sports. “I really hope that the U.S. gambling industry understands that if consumers are exploited, then it’s not good for anyone,” he says.