S-Tier

All of our S-Tier casino sites and sportsbooks are powerhouses in the iGaming scene. This is the highest ranking available, and everything has to be perfect to qualify. You can sign up with S-Tier sites safe in the knowledge that you’re getting the best bonuses, odds, games, payment methods, and more.

  • Bonuses: When you sign up with an S-Tier site, you can be sure of industry-leading welcome bonuses, as well as ongoing reload offers if you stick around and play regularly. These are the most generous bonuses, matching more of your real money deposits in bonus funds.
  • Game Libraries: S-Tier gambling operators are partnered with the biggest names in the casino game development scene. This means you can be sure of slots, table games, and specialty games from award-winning studios.
  • Betting Markets & Odds: Our top-rated operators will cover almost any professional sport you can think of. They even cover emerging niches, such as esports and virtual sports. On top of that, you get fair odds, as these operators don’t take huge margins on every market.
  • Live Casino Action: These brands also focus heavily on live dealer casino games, bringing you closer to the casino floor with immersive table games and gameshows. These operators are powered by the biggest names in this space, ensuring authentic equipment, professional dealers, and high-quality streaming.
  • Betting Features: For an operator to be considered S-Tier, it must offer advanced betting tools and functionality. We’re talking versatile cash-out options, bet builders, profit and loss tracking, and all the pre-game data you need to make informed betting decisions.
  • Payment Options: Our top-rated operators support a wide range of payment methods for your online gambling, including debit cards, e-wallets, cryptocurrencies, and prepaid vouchers. Most don’t charge a cent in transaction fees either.
  • Loyalty Programs: S-Tier platforms also have engaging loyalty programs that gamify every stage of being a player at their sites. Work your way up tiered VIP schemes to bag lucrative perks and bespoke bonuses.
  • Customer Support: Whenever you have an issue, you can rely on S-Tier operators to have your back. These sites generally offer 24/7 customer support. We’re not just talking about live chat agents either, with some still offering telephone helplines.
  • Trustworthiness: Our S-Tier picks operate with genuine integrity. These are licensed and regulated in reputable jurisdictions. They also embrace third-party certification of the fairness of their games, with some also doubling down by embracing provably fair casino games.

A-Tier

If we rank a gambling operator within our A-Tier, you can be sure it’s a high-quality operator that stays ahead of the game. The above-average bonuses, game libraries, and payment options of operators within the A-Tier still get a huge thumbs-up from the ESI team.

  • Bonuses: Welcome bonuses and ongoing promotions at A-Tier operators are incredibly high quality. They are still well above the industry average, giving you strong deposit-match bonuses, free spins, and reload bonuses with competitive wagering requirements.
  • Game Libraries: A-Tier platforms are partnered with many of the top game providers. This gives you access to many of the best slots, table games, and casual games, suitable for any device.
  • Betting Markets & Odds: You can rely on A-Tier online sportsbooks to offer above-average market depth and odds for your sports betting. This includes competitive odds in-play as well as their pre-game lines.
  • Live Casino Action: Operators are shifting their focus towards live dealer games, bringing a great choice of table games and gameshows to your screens. Although they may not quite have the same choice of games as S-Tier brands.
  • Betting Features: The sites offer plenty of betting tools to help you bet smarter, but they may lack some of the functionality that S-Tier platforms can provide.
  • Payment Options: A-Tier platforms offer a range of alternative payment methods, similar to those found in S-Tier brands, but they may not have quite the same depth of options. For instance, an A-Tier site may only support Bitcoin and other major coins, while an S-Tier site may offer deposits and payouts in 30+ cryptocurrencies.
  • Loyalty Programs: Many A-Tier brands have popular loyalty programs that offer long-term benefits to players. Their perks may not have quite the same “wow factor” as those at S-Tier sites, but they are still hugely valuable.
  • Customer Support: The majority of online operators at this tier offer some form of 24/7 customer support, although it is mostly provided via live chat agents. They may also have detailed FAQs and responsive email helpdesks.
  • Trustworthiness: You can play at A-Tier sites safely in the knowledge that they are also licensed by respected regulators. Some are also jumping on the provably fair bandwagon and offering games with 100% decentralized outcomes.

B-Tier

All of the sites that make the cut as B-Tier operators offer solid gambling experiences online. Their game choices and bonuses meet industry standards, but they may lack the added perks you can find at S-Tier and A-Tier platforms. These include VIP programs, reload bonuses, and faster, more versatile payment options.

  • Bonuses: Most B-Tier gambling operators we recommend offer rock-solid welcome bonuses, although they may not be the largest. You may also find that their wagering requirements are slightly higher than promotions listed with S-Tier and A-Tier brands.
  • Game Libraries: Casino operators at this tier can be relied upon to cover a broad spectrum of casino games, even if their game libraries lack the depth of some of our S-Tier and A-Tier brands.
  • Betting Markets & Odds: Our B-Tier online bookies still cover all the high-profile sports events worldwide. They may simply lack coverage of emerging sports or offer limited pre-game and in-play odds.
  • Live Casino Action: B-tier sites often feature dedicated live dealer casinos, but they may only be supplied by a single studio.
  • Betting Features: Most betting platforms will offer modern cash-out functions as a standard feature. But that is as advanced as they get for the time being, with no focus on custom betting tools or controls to monitor odds movements or form.
  • Payment Options: These platforms remain traditional in their approach to payment methods, prioritizing bank cards and wire transfers over e-wallets and cryptocurrencies.
  • Loyalty Programs: B-Tier operators may place less emphasis on loyalty programs – and some may not have one at all.
  • Customer Support: It’s less common for B-Tier operators to offer 24/7 customer support. In most cases, you’ll still get live chat agents available during peak gaming hours, but not overnight. Some may favor email helpdesks and online FAQs instead.
  • Trustworthiness: You can trust every single casino or sportsbook that we recommend at ESI. Even if B-Tier sites may not currently embrace provably fair games or display third-party certification for game fairness from organizations like eCOGRA and iTech Labs, they are definitely secure.

Red Flags That Cause Instant Failure

If a gambling operator doesn’t meet our strict standards, it will not be recommended on our site. In some cases, we also flag casinos or sportsbooks that fail to provide a safe and fair experience. Common reasons for failing include:

  • Reports of delayed withdrawals or refusal to pay out legitimate wins
  • Unfair or hidden bonus terms and conditions
  • Any discoveries of suspicious betting odds movements
  • Poor security measures
  • A history of unfairly voiding valid, winning bets as illegitimate “palpable errors”
  • Unresponsive or unhelpful customer support
  • Patterns of unresolved player complaints
  • Inadequate live betting performance, with slow interfaces or minimal in-play data

Our Commitment to You

We regularly recheck all our recommended operators to ensure they maintain high standards. If a platform’s quality drops, we’ll remove it from our recommended list.

And, of course, your feedback matters – if you have concerns about any casino or betting site we recommend, please let us know by writing to info[at]esportsinsider.com. Your experiences help us maintain accurate, up-to-date recommendations for everyone.

ESI Ranking System
We’ve created a ranking system to help you quickly know how good each gambling platform is. As gamblers ourselves, we know which factors matter most to you, so we follow a best-in-class methodology to test each one with no stone unturned. Once done, we then rank each platform based on the following tiers:
  • A-Tier High-quality sites that deliver a top experience every time. They boast strong performance, nice features, and reliable support, but are just shy of perfection.
  • B-Tier Solid platforms that are worth a spin. They’re safe, fun, and functional, but may be lacking advanced features or have minor drawbacks.
  • S-Tier Reserved for elite operators only. These go well beyond the norm with lucrative bonuses, rewarding promotions, lightning-fast payouts, and a flawless experience overall.
To read more details about how we review casino and betting sites, check out How We Rate Gambling Operators.