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Online Slots Bonus Guide

Online Slots Bonus Guide

Casino bonuses might just be the internet's worst kept secret. If you visit a gambling site or even Google the word 'casino', you'll likely be inundated with bonus offers. From promises of free spins to piles of cash, bonuses are a huge part of gaming. While slot machine bonuses will help you get the most out of your game, they aren't always so straightforward. Luckily, we've created this guide to help you make sense of all the perks online slots sites and casinos are prepared to throw your way.

On top of the bonuses that await you, all our top recommendations also boast:

  • Popular game titles including the top progressive jackpots
  • Air tight security for safe real cash gameplay
  • Responsive support teams available 24/7

If you'd rather cut to the chase then check out our pick of the month, Betway Casino. The #1 online destination for thrilling slots play.

Top Rated UK Casinos for Bonuses

Betway Casino Logo

REVIEW SCORE

9.7

RATED OUTSTANDING

WELCOME BONUS

100% up to £1000

T&Cs Apply
New customers only. Opt-in required. 100% Match Bonus up to £250 on 1st deposit of £20+. Additional bonuses of up to £250 on 2nd deposit of £20+ and up to £500 on 3rd deposit of £20+. 50x bonus wagering applies as do weighting requirements. Credit Card, Debit Card & PayPal deposits only. Irregular gameplay may invalidate your bonus. Full terms apply
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SOFTWARE & COMPATIBILITY

Mega Moolah Jackpot icon Break da Bank Again available Mega Moolah Isis icon

Most Popular Slots

BANKING OPTIONS

97% win rate

0 - 2 Payout Speed

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32Red Casino Logo

REVIEW SCORE

9.3

RATED OUTSTANDING

WELCOME BONUS

150% up to £150

T&Cs Apply
18+ only, New accounts only. Min £10 deposit, debit/credit card and PayPal only. 50x wagering, game contributions vary, max. stake applies. Full terms apply
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SOFTWARE & COMPATIBILITY

Mega Moolah Jackpot icon Mega Moolah Isis icon Jackpot Giant Slot icon

Most Popular Slots

BANKING OPTIONS

96.7% win rate

1 - 2 Payout Speed

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32Red Casino Logo

REVIEW SCORE

9.3

RATED OUTSTANDING

WELCOME BONUS

100% up to £100 + 100 Bonus Spins

T&Cs Apply
18+ only, New accounts only. Min £10 deposit, debit/credit card and PayPal only. 50x wagering, game contributions vary, max. stake applies. Full terms apply
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SOFTWARE & COMPATIBILITY

Mega Moolah Jackpot icon Mega Moolah Isis icon Jackpot Giant Slot icon

Most Popular Slots

BANKING OPTIONS

95.65% win rate

1 - 3 Payout Speed

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Paddy Power Casino Logo

REVIEW SCORE

8.9

RATED Excellent

WELCOME BONUS

Deposit £10 get £50

T&Cs Apply
18+ only, UK& IRL only. Deposits made with e-wallets are not valid for this promo. Bonus wagering x35 on eligible games. Winnings from bonus capped at £500. Spins available after the bonus is redeemed/lost. Full terms apply
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SOFTWARE & COMPATIBILITY

Gladiator Progressive Jackpot Jackpot Giant Slot icon Thunderstruck II icon

Most Popular Slots

BANKING OPTIONS

96.6% win rate

2 - 5 Payout Speed

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  • CASINO

    WIN RATE

    PAY SPEED

    TOP 3 SLOTS

    BONUS

    RATING

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  • 4 th

    Paddy Power Casino Logo

    96.6%

    2 - 5 Days

    Gladiator Progressive Jackpot Jackpot Giant Slot icon Thunderstruck II icon

    Deposit £10 get £50

    T&Cs Apply
    18+ only, UK& IRL only. Deposits made with e-wallets are not valid for this promo. Bonus wagering x35 on eligible games. Winnings from bonus capped at £500. Spins available after the bonus is redeemed/lost. Full terms apply

    8.9

    Claim Now

    Read Review

Why Casinos Offer Bonuses

Why Casinos Offer Bonuses

Traditional casinos are known for treating their players like royalty. Even if you've never been to Las Vegas, you've surely heard about all the comps that casinos offer their guests. A comp is shorthand for complimentary. They can include anything from free drinks, buffet meals, luxury goods, hotel suites, and tickets to shows. Casinos dish out these benefits not just to make players feel like they're wanted, but also to give them an incentive to stay. Why leave if you have a full stomach and a place to stay for the night?

In places like Las Vegas, there's also a lot of competition. It's easy to venture down the street and have your choice of several different casinos. In this situation, bonuses also give players an incentive to walk through the door in the first place. This is the same thinking behind online casino and slot site bonuses. With over a hundred licenced sites in the United Kingdom, internet gambling sites know you have lots of great places to play. That's why sites constantly try to stand out and best each other with increasingly impressive offers. Of course, logistics prevent online casinos from giving you cold drinks, a warm meal, and a comfortable bed. That's why the vast majority of bonuses come in the form of cash. Who doesn't love a little free money, especially when you can transform it into endless fun and possibly riches?

Endless Bonuses

When playing online slots, bonuses are available in all shapes and sizes. Many bonuses come with plenty of fine print but some have no strings attached. You'll find sign up bonuses, which we touched upon earlier. Yet there are plenty of great bonuses for existing players. You can also earn perks from telling your friends about a casino. Keep in mind that bonuses are just one of the many rewards that casinos offer. You can also take advantage of special promotions and loyalty programs whenever you play.

Sign Up Bonuses

Did you know the leading UK slot sites spend most of their marketing and advertising budgets online? While that may seem like a boring business detail, most of that cash goes directly to players. Rather than wow you with flashy adverts, UK slot machine sites know that potential customers love free money. That's why they are prepared to pay you to try their sites. There's no sense wasting cash on billboards and television campaigns when you can cut out the middlemen. The best sites are fully confident that once you try their exciting slots first hand, you'll happily return. That's why they gladly offer generous sign up bonuses. It's a win-win situation for everyone involved.

Sign up bonuses typically consist of free spins, complimentary cash, or a combination of the two. These free spins shouldn't be confused with free games that let you play for fun money. Many sites will give you a couple dozen spins so you can see what the hype is about. You won't even need to place a deposit and you get to keep whatever you win.

Match Bonuses

Most cash sign up offers are of the match bonus variety. When you claim these bonuses, sites will double or even triple the amount of your first deposit. You might see a banner ad for a 100% cash bonus up to £500. That means the casino will double the amount of your first deposit up to a maximum of £500. When you claim this offer, your £10 deposit will give you £20 to play with. You are free to deposit more than the maximum, but you won't be awarded any bonus funds beyond the threshold. Some sign up bonus offers apply to your first few deposits within a certain period of time. It's best to do a little research to find a promotion that works best with your budget and spending patterns.

Match bonuses aren't just available to new players. Sites also have special offers for existing customers. Sometimes a slot machine site will target loyal players to make them feel valued. At the same time some casinos reach out to lure in gamblers who haven't visited in a while. During slow periods like holidays or the middle of the week, casinos tend to be extra generous. Just opt in to receive your casino's email newsletter or check out the promotion page. If you time your deposits to take advantage of great offers, you can really improve your bottom line.

Refer A Friend Bonuses

Refer A Friend Bonuses

There's no better form of advertising than word of mouth. Testimonials from people whose opinions you value are worth infinitely more than the wittiest telly advert. While you might be content to tell your mates about how much fun you've had playing slots, many top gambling sites offer refer a friend bonuses. If you can convince your friend to sign up, sites will give you both some cash for your trouble, even if it's no hassle at all.

Reading The Fine Print

It's hard for some people to believe that gambling sites hand out free cash. While free money might seem too good to be true, in reality terms and conditions make these offers possible. Casinos expect you to play with your cash, which means you won't be able to withdrawal your bonus immediately. In fact, every casino has a rollover rate or wagering requirement. That's the number of slot machines spins you'll need to play before you can cash out your bonus. Rollover rates are standard and are quite reasonable, especially when you consider that you are playing with $ free money in the first place. What's even better is all the cash you can win in the process.

Loyalty Rewards

Do you collect frequent flyer miles or credit card loyalty points? These incredibly popular programs reward you for what you were probably going to do anyway like flying or shopping. That vast majority of slot machine sites also offer some kind of VIP or loyalty program. You can typically earn points whenever you play for real money. You can usually redeem these points for free play, cash, and valuable prizes. The best thing is that enrolment is automatic at most sites.

Casino Promotions

Gambling sites are fully aware just how much competition there is for your entertainment budget. You can easily visit 100 other casinos with a simple swipe of your tablet screen. Not to mention all the video games, movies, fancy dinners, and excursions out there. That's why casinos do their part to keep things exciting and potentially lucrative. It's worth taking a look at your site's latest promotions. Besides cash bonuses, expect to find special tournaments, leaderboard contests, and great prizes like holidays.

Maxing Out Your Bonuses

The best thing about bonuses is you don't necessarily have to limit yourself to just one. It's possible to play at several casinos and claim a sign up bonus at every site. Just make sure you can meet the rollover requirements. Of course, enjoying multiple sites will give you access to even more games and offers. If you are strategic about the way you play and deposit, you can maximize your returns and fun. Just make sure you don't spread yourself too thin since you'll still need to meet the wagering requirements.

We Answer Our Readers Most Common Questions

What are bonuses for online slots?

Online slot bonuses are free money that’s paid out to players for taking a specific action. Generally bonuses are given out for playing specific games, for depositing money, or for betting a certain amount.

How can I make use of them?

You can make use of bonuses at the casino by learning what offers are available and how to capitalize on them. Generally you can begin by depositing money into a new account.

Are the bonuses worth using?

Yes, the bonuses are usually worth using. They are paid out for playing games that you would normally play anyway, and most are easy to qualify for as well.

Can I qualify for them?

Yes, you can qualify for many of the bonuses. Just make the required deposit, play a certain game, or complete the necessary requirement. You might have to wager a certain amount before obtaining the bonuses as well.

Which bonus options are there?

There's a sign up bonus, an endless bonus, a match bonus, and a referral bonus. You can qualify for any of the above bonuses by depositing money, choosing the right games carefully, wagering enough, and inviting friends to play at the same location.

What amount do I have to deposit to get the bonus?

The amount that you must deposit depends on the casino that you're playing at. Most allow deposits of as little as 10 or 20 Euro, and others require a couple hundred before bonuses are offered.

How is the bonus paid out?

Bonuses are paid out through one of the available payment methods. Cheque, bank transfer, credit card, or e-wallet services are normally used.