Online Slots Bonuses: Are they Worthwhile?

Take a trip down Google lane and type “online casino” in the search bar if you want to see the definition of advertising overload. Any time you jump into the online gambling pool, don’t be surprised to find yourself swimming with some of the loudest and most obnoxious advertising campaigns in the world.

With literally hundreds of online casinos competing for your business, it seems like every slots bonus offer seeks to outdo the one you saw last. That $200 welcome bonus is pushed to the margins as a $500 slots bonus slides into view, complete with blinking flash banner and maybe even auto-play sounds or pop-ups if you’re really lucky. Once you figure out which tab the sound is coming from and close it, up comes the next slots offer promising an even more amazing $1,000 bonus!

It feels like a gang-war of drive-by pop-ups sometimes. Ok, it may not actually be that bad these days, but there are is certainly no shortage “colorful” online slots bonuses being advertised on the internet at any given moment. It’s only natural to see all of this and wonder if these offers are so good, why do the casinos need to push these offers so aggressively? Shouldn’t people be flocking to free slots money of their own accord?

That is the question we’ll be answering today. Online casinos are clearly not in the business of handing out free money until their founders go bankrupt. There must be a catch, right? There most certainly is. Read on for the full scoop.

Review Time: How Online Slots Bonuses Work

We have described how casino bonuses work elsewhere, but a quick review is in order for the purpose of today’s discussion. An online slots bonus can come in many forms, but the basic idea is that your casino site promises to add extra “bonus” money to your account in return for you signing up for an account and making a real money deposit of your own.

Note: Not all slots bonuses may be withdrawn. Many online casino offers give you money that may only be used to place bets; you may withdraw anything you win, but may not withdraw the bonus money itself.

Wagering requirements are the big caveat attached to nearly all online casino bonuses. What it means if you are on the hook to place real money wagers of at least some minimum total value before the bonus money and any winnings earned by wagering the bonus money may be withdrawn.

The purpose of wagering requirements is for casino sites to protect themselves and to ensure that customers claiming any given bonus have signed up in good faith with the intention to actually gamble. In other words, they want to make it difficult for anyone to just sign up, claim a bonus and then withdraw everything without ever having an intention to play. Casino sites are looking for customers, not to just give free money to anyone who asks nicely.

Wagering requirements are usually expressed as a multiple of the value of your original deposit and the bonus amount. For example, imagine a 200% bonus with a 30x rollover. This means you need to place a total value of wagers equal to 30 times the deposit + bonus amount.

Continuing our example, let’s say you deposit $50 in order to get a $100 bonus. In this case, you would need to place $4,500 worth of wagers to release the bonus money ($150 x 30). It does not matter how much you win or lose while making those wagering requirements. The only thing that matters is the total value of all wagers placed.

Again, the casino does not care if you win or lose while fulfilling the wagering requirements. If you win a bunch of money, you will still receive your bonus. However, casinos know they have the advantage over the long run and most customers will be down a little after clearing the bonus, which helps to offset the cost of the bonus to the casino. That is how casino sites can afford to offer such large slots bonuses.

Expected Value: What Slots Bonuses Promise vs. What They Deliver

The key to determining if online slots bonuses are worth your while is to consider what these offers promise and compare it to what they actually deliver. What is promised and what is delivered are not always in alignment.

A typical slots bonus promises a bunch of money for doing something you were going to do anyways (gamble). In some jurisdictions, the advertising standards require require bonuses to be explained in certain ways, but still the basic idea anywhere you go is that you are getting a good deal.

What the typical slots bonus usually ends up delivering is an obligation that ends up taking a long time to fulfill and rarely results in you getting much free money. Some casino sites arrange it such that the wagering requirements are too high for most people to ever finish clearing the bonus without losing money over that time.

If a casino has you placing $20,000 in wagers at a game with a 5% house advantage, you’re going to have a hard time coming out ahead before you release that $100 bonus. To be more specific, placing $20,000 worth of wagers into a game with a 5% house edge would end up costing you about $1,000 in losses on average. All that for a $100 bonus – no good.

I’ll grant that is an extreme example, but it shows how you should be thinking when considering whether or not any particular slots bonus is worth your while.

In fact, this is exactly how you should be thinking when considering any bonus. Every bonus comes with an inherent expected value when you compare the wagering requirements, bonus amount and the house edge of the games you are allowed to play while clearing the bonus. We explain this concept in detail at the bottom of our main casino bonuses page.

Basically, you can determine if a slots bonus is worth your time by looking at the terms and conditions to find out what the wagering requirements are and then finding out what the payout rates are for that casino’s slots. This information is all available at casinos that are headquartered in regulated jurisdictions such as the UK.

We wrote a big post about slots payout rates in the past, so I’ll refer to that post for some numbers to help explain how this all works. The following figures regarding payout rates are dated from last year, but those numbers should still be pretty close to the same today.

We can see from that post that some online slots offered payout rates of 94.91% as of June of last year. That means the house has an advantage of 5.09% on all slots games. For every $1.00 you spend on slot machines, you can expect to lose an average of $0.0509. Or for every $100 you wager, you will end up being down $5.09 on average.

The phrase “on average” is a key point to note there. The house advantage is calculated based on the long term expected results. In any given session, you will most likely win or lose more than that amount. This is just a general number over the long term. The longer you play, the closer your real world results will approach the expected results.

Now, let’s look at another bonus and use this approach to determine if a 200% slots bonus with a 30x rollover is worthwhile.

If you deposit $50 while claiming this bonus, you will end up with a total bankroll of $150 and wagering requirements of $4500 ($150 x 30). The house advantage as of last year at that casino was 5.09% and is probably similar to that today.

Here’s how it works out:

  • You deposit $50 and get $100 for a total bankroll of $150
  • Your total wagering requirements are $4,500
  • The house advantage is 5.09%
  • 5.09% x $4,500 = $229.05
  • Thus, you should expect to lose $229.05 on average while clearing this bonus
  • Your net gain works out to -$129.05 ($100 in bonus cash minus $229.05 in expected losses)

In this example, the slots casino bonus is not worth your time or money. The clearing requirements combined with the house advantage will end up costing you more than the value of the bonus on average.

Again, this is just a long term average. It is entirely possible that you will come out way ahead after clearing this bonus. That’s how casino games work – sometimes you go hot and win a bunch of money. However, if we look at this from a purely mathematical point of view, this casino bonus is not a good deal. Most people will end up losing money by claiming this bonus.

Let’s look at a couple other examples.

Example 1: 100% up to £150

  • Deposit £100: Get £100
  • 20x rollover
  • Total wagering requirements: £4,000
  • House advantage as of May 2016: 4.7%
  • Expected losses: £4,000 x 0.047 = £188
  • Expected net gain after claiming bonus: £100 – £188 = -£88
  • Verdict: Not worth it

Example 2: 100% up to £100

  • Deposit £100: Get £100
  • 30x rollover applied to bonus amount only
  • Total wagering requirements: £3,000
  • House advantage as of September 2016: 3.73%
  • Expected losses: £3,000 x 0.0373 = £111.90
  • Expected net gain after claiming bonus: £100 – £111.90 = -£11.90
  • Verdict: Not worth it, but very close to breakeven

So are slots bonuses worth it?

Most slots bonuses are not worth your time. As we can see from the expected value calculation above, you end up losing money more often than not. Casino bonuses look nice at first glance, but a few simple calculations show that you would be better off not claiming the average casino bonus.

You can see from our examples above that sometimes a casino bonus can come very close to being a breakeven proposition. The 888Casino bonus as described above works out to a net expected value of negative £11.90. That is not a terrible amount of money to spend considering the extra play-time you get just by wagering the bonus. There is at least some justification there if you decide to just have fun with it and hope to get lucky while completing the wagering requirements.

And also, I am not picking on the casinos mentioned by name above.  William Hill and 888 are all great casino sites with sterling reputations. Their bonuses may not be the best deal in the history of deals, but we should give those casinos some credit for clearly explaining their bonus terms and making their slots payout rates publicly available.

There are many casinos that do not operate in such a transparent manner. I cannot begin to explain the number of times I have searched for the payout information of certain lesser-known online casinos only to find that information impossible to find.

To sum it all up, the average online slots bonus is better off avoided if your primary goal in gambling is to make the most of every mathematical advantage you can find. If your number one goal is to just have fun and throw caution to the wind, the have at it. Just remember to do your research, understand the odds and to always play within your bankroll.