Ryan's Thoughts"The popularity of online slots has led to a huge increase in demand, and software providers have taken advantage, supplying a huge number of online slots to keep players interested."
HeadlineCasinos.com helps you explore all of the best slots, the casinos that offer them, and the best bonuses and free spins you can use to play.
Online slots at a glance:
- First real money online slot launched in 1994.
- Slots make up 80%+ of game play at online casinos.
- 2500+ real money online slots currently.
- More than 10 new online slots are released every month.
- 50+ online slot providers currently.
- Biggest jackpot win on slots: €17,879,645 by Joe Heywood on Mega Moolah on 6th October, 2015.
- Over a dozen progressive jackpot wins since 2015.
The Best Slots Casinos and Bonuses
Types of Slots Bonuses and Promotions
Almost every bonus available at an online casino can be used to play online slots, including:
Free spins bonus
You get a free spin on specific slots or the entire range of slots, depending on the casino operator. It is available as a no deposit bonus and also as a match bonus.
Match bonus
Available to new and existing players: the casino matches the amount you deposit, which is usually a percentage of your deposit amount.
No deposit bonus
Available exclusively to new players on sign-up before they make a deposit. The three types are:
- Regular no deposit
- Free spins
- Free play with time
Bonuses and promotions come with terms and conditions to ensure fair use and prevent fraud or abuse. The most prominent condition is the wagering requirement. You have to know the wagering rules for a bonus before you use it, otherwise you invite penalties including:
- Cancellation of the bonus
- Loss of winnings from the bonus
- Suspension or termination of account
Types of online slot machines
There are a large number of online slots today. You can categorise them on the basis of:
- Themes
- Number of reels
- Jackpots
- Coin size
The following are the major types of online slots you get at the online casinos:
- Classic slots
- Video slots
- Bonus feature slots
- Slots with free spins
- Penny slots
- Progressive slots
- Branded slots
Classic Slots
These are 3-reel slots with a classic look and feel resembling the games available at land-based casinos. The common symbols on the reels include fruits, the word BAR, bells, the number 7 and also the wild symbol. They lack features like Autoplay, but they may have bonus rounds or even a jackpot.
Video Slots
Video slots form the majority of the games at online casinos. They have 5 reels and multiple paylines and loads of features. The features available include high quality graphics and animations, wild symbols, scatter symbols, multipliers, bonus games, free spins, and reasonably high payouts. Some of them also have a progressive jackpot.
Bonus Feature Slots
Some slots come with special bonus features apart from the wild symbols, scatter symbols and multipliers. They include:
- 243 ways to win: You win when 3 matching symbols land anywhere on the reels from left to right or the other way round.
- 1024 ways to win: It works the same as 243 ways to win. The wins on active paylines concept is replaced by the ability to pick up wins on any symbol combination from left to right.
- Win both ways: You win regardless of whether you land matching symbols from left to right or right to left.
- Reel-based bonuses: They help you pick multiple wins in a single spin and include:
- Cascading reels
- Reel re-spins
- Tumbling reels
- Rotating reels
- Gamble feature: It gives you a chance to double your winnings from a spin or lose it all.
There are also bonus games. These are special games that are triggered within the slots. There are different kinds of bonus games, including pick-me-up rounds, spinning the wheel given and others.
Slots with Free Spins
A number of slots offer free spins as the bonus round. Some games have a simple free spins round while others, like Microgaming’s Thunderstruck II, has multi-stage free spins: you progress across the stages as you land more of these bonus rounds.
Penny Slots
Penny slots are fun and allow you to bet a minimal amount per spin. They attract players because:
- You do not need a lot of money to play them.
- You can use an average-size bankroll to play for a long time if you manage your money wisely.
- You tend to win less, but more frequently.
- Even if you lose a spin it isn’t too much money.
The problem with penny slots is also related to the one big advantage of playing them – you can play for a long time but, in most cases, you don't win as much. You may also not realise that you are actually losing money over time. This is more obvious if you bet the maximum amount.
Progressive Slots
These slots come with a progressive jackpot that is triggered only when you are placing the maximum bets. There is a jackpot meter that gives you the latest value of the jackpot.
There are different kinds of progressive slots available:
- Standalone progressives:The jackpot pool is from the wagers placed on that machine; it is not connected to other machines.
- Local progressives: The jackpot pool is built from contributions from machines in the casino you are playing at.
- Networked progressives: The jackpot pool is created from multiple casinos across the world where the game is present. That is why networked progressive slots build their high jackpot values very rapidly and the payout, when it happens, is also enormous.
Branded Slots
Slots providers create branded slots by collaborating with reputed brands from different streams of business, including Hollywood and the world of comic books. Players are thus able to play slots featuring their favourite superhero or movie character.
The following are 4 major software providers who have inked branding deals with some of the most well-known names in the comic-book and entertainment industry.
Microgaming
Microgaming has collaborated with Universal Brand Development for the release of multiple branded slots including:
- Tomb Raider, which was among the first branded slots from Microgaming
- Hit Man, another of the early Microgaming branded slots
- Jurassic Park, themed on the blockbuster of the same name
Other branded slots from them include Game of Thrones, themed on the HBO series, Bridesmaids, based on the blockbuster Hollywood movie of the same name and Bullseye, based on the hit TV show presented by Jim Bowen.



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Playtech
Playtech was one of the first to collaborate with Marvel Comics to bring to players slots featuring the different Marvel superheroes, including:
- Spiderman
- Iron Man
- The Incredible Hulk
However, this collaboration ended as of 1st April, 2017. Currently they have signed a branded content deal to license and develop DC-branded film and television material including Batman and Suicide Squad. It has also collaborated with Hollywood production houses to release games like Gladiator.


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NetEnt
NetEnt has exclusive partnerships with some of the biggest names in entertainment from Hollywood to bring to players games such as Guns ‘n Roses, Aliens, the South Park series, Scarface and Motorhead. Companies they have collaborated with include:
- 20th Century Fox™
- South Park Digital Studios™
- Universal™



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Novomatic
Novomatic’s GreenTube has a branding deal with GVC Holdings of London to offer 70 games from GreenTube on GVC’s poker and casino sites, including Bwin, PartyPoker, PartyCasino and Gamebookers.

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Online Slots Providers
Every major software provider, whether they're more established, such as Microgaming, or new to the industry, have a bank of high quality slots.
Below we provide you with a brief overview of the major players. You can categorise slots developers into 3 types, primarily:
- Traditional land-based slots manufacturers
- Online casino pioneers
- Niche developers
Traditional Land-based Slots Manufacturers
A number of developers initially provided slots for land-based casinos. These include, among others:
You can find their games at all the major online casinos on our list, including brands like Ladbrokes, Paddy Power and many others.
Online Casino Pioneers
Since 1994 Microgaming has led the way in casino game development. Other casino software providers from that time include:
Along with Microgaming, these companies are considered to be the pioneers of the online casino industry. Each of them have amazing games and have all remained at the top by staying relevant and adopting new technology to engage in innovation-driven development.
Niche Developers
In the last decade or so there has been a new crop of developers that have targeted niche segments of the online casino market, with slots being a major share of their offerings. They include:
- Rival Gaming
- BetSoft Gaming
- Play’n Go
- Elk Studios
- Yggdrasil Gaming
- High 5 Games
- 2 by 2 Gaming
- Blueprint Gaming
- Thunderkick
- IGT
- NextGen Gaming
- Quickspin
- Rabcat
Another niche segment that developed within the online casino industry was the live dealer casino, where the dealer is a real person. Older providers like Microgaming and others offer live dealer games, but there are a few new software providers that focus exclusively on this segment. These include:
- Evolution Gaming
- Extreme Live Gaming
- Ezugi
- Portomaso Gaming
- Global Gaming Labs
Slots Tips for Beginners
Slots are fun and very easy to play, which is why they are so popular. Here are a few tips to check out if you are a beginner at online slots.
Zeroing in on the Right Casino for Slots
Cross the following off your checklist when searching for the right slots casino:
- Ambience
- Software provider
- Range of slots on offer
- Quality of graphics and overall features
- Payment and customer support
Play in Practice Mode
Practice your game before playing for real money. Read reviews from experts and customers for a better idea of the game.
Check the Security and Safety Aspect
Check for the licensing and regulation info on the home page, it reflects the operator’s transparency. You then don’t have to worry about the safety and security of your money and personal details.
Finding the Right Play Mode – Download or Free Play?
The mode of play is mostly about what works best for you. The quality is nowadays the same in both instant play and download modes, of course in instant play you save on memory space. Latest games are available in instant play mode only.
Online Slots – Know Your Game
Make an effort to know more about your favourite slot. Knowing how the bonus features and the payouts work helps you plan your wagering and play better.
Use the Right Payment Method
Use a payment method that you are familiar with and which supports deposits and withdrawals. Playing at a casino with a wide range of payment options is a safer bet for you have more methods to choose from.
Winning at Online Slots
There is no strategy to win at slots. However, there are a few things you can do:
- Manage your bankroll properly.
- Understand the game thoroughly.
- Work out the expected returns on your investment before you play.
- Target slots that are popular - they are popular for a reason.
- Research the bonuses available thoroughly.
How to Pick a Winning Online Slot
The most important elements to consider when picking a winning slot, apart from popularity, include:
- Return to Player (RTP)
- Kind of jackpot on offer, if any
- Hit frequency
5 Quick Tips for Beginners
Here are 5 quick slot tips if you are a beginner:
- Bet safe and bet wise.
- Play patiently: the house has the edge, not you.
- Don’t play with money you don’t have, you could end up with debt or gambling addiction.
- Join a VIP club for slots for access to privileges like bigger bonuses and more.
- Choose your game wisely: a high RTP game with more bonuses is a good bet.
How to Read a Slot Machine Paytable
A paytable gives information on payouts for the different winning combinations. Always check the paytable before you play. You can do this by clicking the relevant button for information. The paytable is usually listed out last, beyond the screens with information on the symbols and bonuses.
This is what you find in the paytable for a slot game, e.g. NetEnt’s Starburst:

- The positions on the reels where the symbols must land for a payout to be triggered.
- The possible payouts for each payline. General rules suggest that the symbols must be directly under the payline.
- The payline, a straight or zig-zagged line that crosses the different symbols on the reels that have the winning combination.
- The first of the symbols in the winning combination must be on the first reel. There can be exceptions but these will be clearly stated.
- Wild symbols that substitute other symbols also feature in the payline.
For each game the rules specific to ensuring the payout are listed along with the paytable. As in the above image they are listed below the paytable.
Slots FAQs
Land-based slots have been around for much longer than online slots. Online slots offer many benefits but there is one big thing missing – the human element. This is why land-based slots are still popular. Of course, online slots have their own benefits, such as:
- The comfort of playing from home at casinos outside your city.
- Incredible bonuses and promotions.
- Frequent and higher payouts.
- Bigger progressive jackpots.
The first slot was the Liberty Bell, created by Charles Fey in 1887. Next came video poker, followed by the invention of the next slot machines with the classic fruit symbol, created by the Bell Fruit Gum Company.
Electromechanical slots first came in the 1960s, and were replaced by the electronic machines in the 1980s. The random number generator was the next big thing and led to the birth of the progressive jackpot. Online slots came in the 1990s and now in the 21st century we have mobile slots.
Technically, there aren't many rules that govern slots play. There are rules that govern how wins are determined. For instance, most slots allow wins only on symbol combinations across the reels from left to right. There are also rules governing the game features but these are more guidelines than rules.
There is no particular strategy to win at slots, it is a game of chance. However, a few things can help minimise your loss frequency:
- Choosing the right game.
- Understanding the payout tables.
- Efficient bankroll management.
- Avoiding credit-based play.
- Playing with restraint.
- Knowing when to walk away.
Both options have their own merits, but the world is rapidly moving away from the download option. Platforms like Microgaming continue to offer games in both download and no-download modes, but technology has evolved and the no-download option is being offered comprehensively.
The best option today is the hybrid casino, where you get the multiplatform option. Multiplatform casinos are rapidly gaining in popularity because they offer games from all the leading software providers together, giving you a wider range of the best games to choose from.
Now you can play slots directly from your mobile device on the go. This is a huge advantage over online slots, which only allow you to access the games on your computer or laptop, from a designated location.
The range of games is still greater using online slots, but the mobile industry is catching up. Microgaming, for instance, offer more than 350 of their games on the mobile platform. These games are as impressive as their online counterparts, offering the same high quality gameplay, payment and customer support you would find at a regular online casino.
The RTP is the amount of money a player can expect to win back from the total amount wagered on a slot. It is described as a percentage value and is directly related to the house edge. The higher the RTP, the lower the house edge. For instance, if a game has a RTP value of 95% the house edge will be 5%.