If you’re a seasoned gambler, whether at online casinos, brick-and-mortar ones, or simply with friends, you’ll know that sometimes you win, and sometimes you lose. 

If you play responsibly, you’ll always put a limit on how much you bet, so that you can have fun without losing more than you can afford. However, not all players are so responsible, and there have been some really gargantuan losses throughout history. 

Read on to find out the top 5 greatest gambling losses of all time, and how they went down.


Maureen O’Connor is the only woman on this list, but more notably, she was serving as the mayor of San Diego at the time of her great gambling loss! 

$13 million is a lot of money, but considering that she gambled over $1 billion, it’s actually quite impressive that she kept her losses so low. O’Connor’s gambling habit was clearly a serious one, to the extent that she had to borrow $2 million from her second husband’s charitable foundation, only to spend it all on Video Poker. 

However, we do O’Connor a disservice if we only remember her for her massive losses. She served well as mayor and achieved much in her career through hard work and merit. And to her credit, she paid her gambling debt in full—which was no small feat.


Like Maureen O’Connor, former Australian billionaire Harry Kakavas’ loss of $20.5 million is actually minimal when you consider he gambled $1.43 billion. His losses racked up over a two-year period between 2012 and 2013, exclusively at the Crown Casino in Melbourne.

When faced with the consequences of his gambling, the real-estate mogul attempted to sue the Crown at the High Court of Australia on the grounds that they exploited his “pathological urge to gamble”. However, he did not win the case, as the judge deemed Harry was capable of rational decision making. 

But it’s clear that Kakavas had a gambling addiction that went back many years. Back in 1998, he spent four months in jail for defrauding a large Australian company to the tune of $220 000, using the money to fund his gambling problem. 

A regular at the Crown Casino, Harry saw this as his rock bottom and excluded himself from gambling there. But he couldn’t keep himself away from the Baccarat tables and was later spotted losing millions in Las Vegas. It was then that the Crown Casino allegedly enticed Harry back to their tables, leading to the ensuing losses. So, is the Crown in the wrong? We’ll leave you to make up your own mind.


Charles Barkley is possibly the most famous name on this list. Unlike the previous two, the 11 times NBA All-Star was not a prudent gambler. 

Despite his massive success as a basketball star, he gambled away almost his entire fortune of $30 million dollars. Ever the high-roller, Barkley has admitted to losing $2.5 million in a single Blackjack session. However, while Barkley certainly had a problem, he also seems to have found more joy out of the game than many of the others on this list. 

He played at lots of different casinos, and enjoyed a variety of games, from Baccarat to Blackjack to Dice to Roulette. For him, it was never about winning loads of money, but more about the thrill of the action. He understood losses were part of the game. 

Barkley has learned a little about responsible gambling over the years. He took a break from it for some time, and while he is back at it, he no longer gambles more than he can afford. 


Archie Karas is one of the most famous gamblers of all time, and despite being one of the biggest losers, he also holds the record for the longest and largest winning streak in gambling history. 

In 1992 he was destitute, arriving in Las Vegas with $50 in his pocket. He secured a $10,000 loan from an acquaintance and turned this into more than $40 million by early 1995. 

Legend has it that once he got to a $7 million bankroll, he would simply lay out the money on a table and wait for an opponent to approach him. His games of choice were Poker, Baccarat, and Dice.

However, this massive winning streak was bound to end at some point, and Karas made more and more reckless bets, bargaining with the casino to let him bet way above the limit. He lost every last million of his winnings over 3 weeks. 

From one of the biggest winners of all time to one of the biggest losers, Archie Karas is certainly an iconic figure in the casino world.


Terrance Watanabe was the son of a successful businessman, inheriting the Oriental Trading Company when his father died in 1977. However, he was more interested in gambling than business, and sold the company in 2000 to turn his attention to Baccarat and Blackjack. 

In 2007, Watanabe went on a year-long gambling spree in Vegas, primarily at Caesar’s Palace. He bet a staggering total of $835 million and lost $127 million. Watanabe’s devastating losing streak is reportedly the biggest Las Vegas has ever seen.

Watanabe was addicted to more than just gambling. According to witnesses, he was drinking two to three bottles of vodka a day, as well as allegedly using more serious substances such as cocaine. 

Caesars Entertainment Corporation, who owns Caesars Palace, paid a $225 000 fine for allowing Watanabe to continue gambling in an intoxicated state. Watanabe still owes $15 million to this day and faces jail time if he doesn’t pay up.


Playing real money online casino games or spending time at a land-based gambling venue is hugely enjoyable and incredibly rewarding too. However, it’s crucial to set your limits before a gambling session and never to go above them. If you are interested in trying out a brand new online casino, you will find the best ones on our dedicated pages for new online casinos.

Have fun, but always remember to gamble responsibly!

Nakoa Davis