Biggest Online Gambling Sites 2024

  1. 1
    100% / £ 50Welcome Bonus
    Full terms apply | +18 | #ad | New customers only - BeGambleawareNew UK Players only. 18+erms Apply. Automatically credited upon deposit. Cancellation can be requested. First Deposit Only. Max. Bonus £50. Maximum amount of Free Spins is 50. Game: Book of Dead, Spin Value: £0.10. WR of 30x Deposit + Bonus amount and 60x Free Spin winnings amount (only Slots count) within 30 days. Max bet is 10% (min £0.10) of the free spin winnings and bonus amount or £5 (lowest amount applies). Spins must be used and/or Bonus must be claimed before using deposited funds. Deposit/Welcome Bonus can only be claimed once every 72 hours across all Casinos. Bonuses do not prevent withdrawing deposit balance. Bonus Policy applies.A minimum deposit of £10 applies.Mr Gamble always insists that players gamble responsibly
  2. 2
    100% / £ 100Welcome Bonus
    Full terms apply | +18 | #ad | New customers only - BeGambleawareNew UK Players only. 18+T&Cs apply. New cust only. Deposit & Place a Bet within 7 days, and settle a £10 minimum bet at odds of 4/5 (1.8) or greater, to be credited with 3x £10 Free Bets: 1 x £10 Horse Racing, 1 x £10 Free Bet Builder and 1 x £10 Football. 7 day expiry. Stake not returned. 18+ BeGambleAware.org.A minimum deposit of £10 applies.Mr Gamble always insists that players gamble responsibly
  3. 3
    100% / £ 100Welcome Bonus
    Full terms apply | +18 | #ad | New customers only - BeGambleawareNew UK Players only. 18+18+. New Players Only. Min Dep £20. Offer: 100% of 1st deposit up to £100 + 100 Spins on Big Bass Bonanza. Spins expire after 23:59 GMT on day they are credited. Spins winnings credited as bonus, separate to Cash funds, & subject to 35x wagering of bonus + deposit amounts. Bonus funds expire after 21 days. Affordability checks apply. Terms Apply. BeGambleAware.org.A minimum deposit of £20 applies.Mr Gamble always insists that players gamble responsibly
  4. Bonus code: WINO100
    4
    100% / £ 100Welcome Bonus
    Full terms apply | +18 | #ad | New customers only - BeGambleawareNew UK Players only. 18+18+ | Please play responsibly | www.begambleaware.org | 1st deposit only | min deposit £10 | max bet with bonus £2 | max bonus £100 | X40 wagering | bonus spins valid for selected games only | X40 wagering on bonus spins winnings | expires within 24 Hours | User Agreement & Bonus T&Cs apply.A minimum deposit of £10 applies.Players must use the bonus promotion code WINO100 in order to apply this bonus.Mr Gamble always insists that players gamble responsibly
  5. 5
    100% / £ 300Welcome Bonus
    Full terms apply | +18 | #ad | New customers only - BeGambleawareNew UK Players only. 18+18+. New ID Verified players only. Free Spins awarded as bonus credits. Up to £10 bonus credit. The max win of £10 bonus credit can be used for 250 spins at £0.04 per spin. Win paid as bonus credit. 40x wagering requirement. 7 day expiry. £50 max withdrawal from bonuses without a deposit across all Intouch Games Accounts; mFortune, Mr Spin, Dr Slot, PocketWin, Casino2020, Cashmo, Bonus Boss, Jammy Monkey. T+Cs apply. BeGambleAware.orgA minimum deposit of £10 applies.Mr Gamble always insists that players gamble responsibly
  6. 6
    100% / £ 50Welcome Bonus
    Full terms apply | +18 | #ad | New customers only - BeGambleawareNew UK Players only. 18+: Full T&Cs apply. New reg only. Opt in & deposit £10, £25 or £50 within 7 days & further 7 days to wager cash stakes 35x to unlock reward (£50 on 2 deposits). 3 day exp. Wagering/game contributions vary. 25 wager-free spins x10p to added to Big Bass Splash with each qualifying deposit, 3 day expiry. 18+ BeGambleAware.org.A minimum deposit of £10 applies.Mr Gamble always insists that players gamble responsibly
  7. 7
    100% / £ 100Welcome Bonus
    Full terms apply | +18 | #ad | New customers only - BeGambleawareNew UK Players only. 18+Welcome bonus package on first 3 deposits 1st Dep. Min £20. 50x wagering (bonus & deposit). (Exc PayPal) max bonus to cash 5x. 20 Free spins. 35x wagering. Max bonus to cash £30. Claim once. See full T&Cs for 2nd & 3rd Deposit offers. Full T&C's apply.A minimum deposit of £20 applies.Mr Gamble always insists that players gamble responsibly
  8. 8
    100% / £ 50Welcome Bonus
    Full terms apply | +18 | #ad | New customers only - BeGambleawareNew UK Players only. 18+A minimum deposit of £10 applies.Mr Gamble always insists that players gamble responsibly
  9. 9
    100% / £ 250Welcome Bonus
    Full terms apply | +18 | #ad | New customers only - BeGambleawareNew UK Players only. 18+18+. New players only. Min Dep £20. Max Bonus Bet £5. Offer: 100% of 1st deposit up to £250 + 100 Yoo Spins on Starburst, Book of Dead, Fire Joker, Gonzo's Quest, & Big Bass Bonanza respectively (first 20 credited on 1st deposit; rest credited at 07:00GMT at 20/day). Spins expire after 23:59GMT on day they’re credited. Winnings from each 20 spins capped at £50 & credited as bonus. Bonus funds expire after 30 days, are separate to Cash funds, & subject to 35x wagering of bonus + deposit amounts. Only bonus funds contribute to wagering requirements. Bonus funds can only be used on slots. Full Terms Apply. Play responsibly. BeGambleAware.orgA minimum deposit of £20 applies.Mr Gamble always insists that players gamble responsibly
  10. 10
    100% / £ 300Welcome Bonus
    Full terms apply | +18 | #ad | New customers only - BeGambleawareNew UK Players only. 18+18+ New players only. Min Dep £20. Max Bonus Bet £5. Offer: 100% of 1st deposit up to £300 + 100 Zee Spins on Starburst (first 10 credited on 1st deposit; rest credited at 07:00GMT at 10/day) + 500 Zee Points. Spins expire after 23:59GMT on day they’re credited. Winnings from each 10 spins capped at £50 & credited as bonus. Bonus funds expire after 30 days, are separate to Cash funds, & subject to 35x wagering of bonus + deposit amounts. Affordability checks apply. Full Terms Apply Play Responsibly. BeGambleAware.orgA minimum deposit of £20 applies.Mr Gamble always insists that players gamble responsibly

The largest online casino in the world is open to debate. With thousands of places to spin the wheel and fortunes at our fingertips, we’re truly spoiled for choice. There are advantages of using smaller, niche casinos – like taking advantage of signup bonuses that offer a wealth of opportunities.

Your preference, however, might be something you’re more familiar with. Using the biggest online gambling sites has its perks. A slick user experience, coupled with the knowledge that they’re safe, regulated and often offer the opportunity for a dabble on the sports if you’re that way inclined too.

Why Trust Mr. Gamble?

For the safety of players and to keep operators accountable, the team at Mr. Gamble implements a world-class evaluation process for all online casinos. The team incorporates a strict due diligence process for listing casinos on Mr. Gamble by verifying the operating regions of casinos and the validity of local licenses, among other aspects such as customer service, game selection, banking methods, and bonuses.

Our editorial policy includes fact-checking all casino information while including real-world data to provide the most relevant and helpful guide for readers around the world. At Mr. Gamble, the players’ safety and satisfaction are our top priority — you can rely on us to get the best possible offers from licensed online casinos.

It’s not easy to spot the biggest online gambling sites, but we’ve done the job for you to make it all a little bit easier for you. We’ve had a look at some of the world top online casino and here’s just a few of the best for you.

What’s the Largest Online Casino in the UK?

The largest online casino in the UK is likely Entain. While you might not recognise the name, Entain is one of the world’s largest gambling companies and has lots of very familiar names under its umbrella.

You might be most familiar with high-street staples Ladbrokes and Coral both of which have popular online casino sections too. Entain’s casino led brands include PartyCasino, Gala Spins, Gala Casino and even websites like Gala Bingo have a dedicated slots section where you can have a spin too.

Do you know what all of these brands mean? More free spins, more sign-up bonuses and given that they’re all under the same umbrella, the registration process and approval on registration should also be lovely and easy.

You may have heard adverts for Foxy Bingo and Foxy Games on your radio too, which you’ll now be unsurprised to hear are also from Entain. Each of the biggest online gambling sites listed above have a great variety of table games, slots and live casino too. If you’re someone that enjoys a bet on football as much as they do a quiet night in on Fishin’ Frenzy then Coral and Ladbrokes may be best for you.

If you fancy yourself as Daniel Negreanu and play a bit of online poker, then you’ll be happy to know that PartyPoker has a pretty comprehensive library of slots as well as one of the industry’s most recognised poker downloadable software. Under Entain, the biggest online casino UK, you’re likely to find at least one site for you. Whether it’s bingo, poker, slots or roulette – there’s a site for everyone.

What’s the Biggest Online Casino in the World?

The world's top online casino is Flutter Entertainment. Just like Entain, you might not be too familiar with the biggest online casino in the world due to the name. But underneath Flutter there’s another array of international brands which you’ll be all too familiar with.

In the UK, Sky Betting & Gaming, Paddy Power, Betfair, Pokerstars and Tombola are all brands we’re well aware of. Then there’s the US giant FanDuel as betting and gaming gets legalised more and more on a state-by-state basis.

Flutter’s brands each have a wide variety of games available to punters. Looking closer at Paddy Power, PP Games has all of your favourite slots. Fishin’ Frenzy, Reel King, Age of the Gods, Fishin’ Bonanza, Sahara Riches and more all feature prominently alongside Table Games, Megaways jackpots, Bingo and Live Casino too.

Little known this side of the pond would be Junglee Games, another one of Flutter’s arms – the fastest-growing skill games company in India and South-East Asia. The casino is a little different from what you’d find over here – given legislation around skill-based gaming and the RNG mechanics of slots. You’re able to play Rummy (something firmly embedded into Indian culture), plus ‘Spin-n-go’ and ‘Beat The Legend’ Rummy too. Junglee has over 500 employees and a whopping 50 million users across South East Asia.

It's not just Junglee who you might not know. Take Adjarabet, the prime sponsor of both the Georgian national basketball team and national water polo team as well as holding name rights to the Adjarabet Arena, the home of Georgian football champions FC Dinamo Batumi. They’ve been going for over 20 years, and have well over 1,000 employees that help bring Flutter’s famous Betfair Exchange, plus poker, casino and sports to Georgia and Armenia too.

Frequently Asked Questions

Which online casino has the most slots?

While that’s just one example, we’re lucky now to live in a time where the best online gambling sites simply wouldn’t exist if they didn’t have a wide variety of games and slots. Premium slots and the most well-known titles are often across each and every site, and with Megaways and Progressive Jackpot slots there’s games that are shared between sites to give you the chance to win even bigger prizes.

How do I deposit with the best online casino?

There are several different payment options with all the best online casinos. Some of them that we’ve covered in this article will typically use the more traditional means, including debit card, bank transfer, and e-wallets such as Neteller and PayPal.

On the biggest online casinos, cryptocurrency is something that’s not necessarily supported yet. Due to the complexity (or non-existence) of regulation around the use of cryptocurrency around the world it’s something that casinos that offer in multiple regulated jurisdictions are cautious about accepting.

Hopefully, this shouldn’t be an issue, though, as fast withdrawals and deposits are a staple to run a good service and stay ahead of competition.

Do the biggest online gambling sites also offer sports and bingo?

Absolutely, they offer sports, bingo, as well as live casino games in addition to their large slots collection. To be the world’s biggest, you have to have more than just a few pretty slot machines on a website. 

Make sure you have a good look on each site, to find the best sign-up bonuses, be aware of any rollover requirements, and choose the best site for you.

    • avatar-Hyun Lee
      Hyun LeeOnline Casino Expert
      Hyun Lee leads all content efforts at Mr. Gamble. Player safety is his number one priority — he demands transparency and fair conditions from operators while establishing Mr. Gamble as a trusted source for all online casino information...
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      Paavo SalonenCo-Founder & COO
      Paavo Salonen is the co-founder and COO of Mr. Gamble. His passion for all things casinos led to building a world-class iGaming company. Having over a decade of experience, he knows exactly what gamblers are looking for — he shares his wealth of knowledge in all the articles Mr. Gamble publishes...