400% Casino Bonus UK

By Ville Saari. Updated:

Bonus offers come in all shapes and sizes. Basically every casino has one and finding the biggest ones might turn out to be a bit difficult. But, that is what Bojoko is for.

The seasoned casino experts here on Bojoko can help you find the bonus offers that you want. We have tested and reviewed the casinos, so you know what they have in store and what playing there is like. Let Bojoko show you how to get a 400% deposit bonus.

Right here, you can find all the big bonuses, those sweet deals that are hard to come by. Below, you can see every UK casino that we have reviewed with a 400% casino bonus.

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  1. 400%/£40
    1st deposit bonus
    Unibet casino review »
    1st deposit bonus 400%/£40
    Bonus code -
    Minimum deposit for bonus £10
    Minimum deposit £5
    Launch date 01/1997
    Unibet is one of the most well-known international brands in the gaming industry and has also gained great popularity in the UK. Kindred Group ltd, the company behind Unibet is ... Unibet casino review »
    Play here » New customers only, 18+. Min deposit £10. Money back as casino bonus. Bonus expires after 30 days. Wagering requirements apply - 50x. Further T&C's Apply. Full and Bonus apply. BeGambleAware.org.

UK casino websites with 400% deposit bonuses

Best UK sites with a 400% first deposit bonus

Are you ready to get your hands on a 400% bonus from the best casino sites? Here, we have highlighted some of the finer casinos that have big bonus offers.

As these 400% bonuses are a rare treat, there are only a very limited number of casinos in the UK that have them.


Unibet has a big 400% casino bonus

Unibet is a legend, there's no doubt about that. Founded all the way back in 1997, they are one of the longest-running online casinos in the world. And you don't get to be this old without knowing what players want.

One of the best features about this casino is that they are the perfect all-rounder. They have slots, table games, sports betting, bingo, poker and pretty much everything gambling-related under one roof. You really don't have to make a decision on where to play which game, as they are all right there.

Unibet also knows how to welcome a player. Their offer is a spicy one.

You can read more about Unibet by checking the casino review, or hop right on in and claim the bonus.

Play on Unibet »

What is a 400% casino bonus

A 400% casino bonus is a huge gift from a casino that comes with certain terms and conditions. The basic idea is that you get four times your deposit in bonus money to play at the casino.

Getting so much bonus money compared to your deposit is a big deal, so casinos are a bit stingy about it. It is not a common offer, and a casino website with 400% bonus is a tall order. Which is why you might want to take a closer look at one when you see them in the wild.

Deposit £10 and the casino will give you £40 of bonus money

Big bonus percentages often translate to small maximum bonuses. It is not good for business if you keep handing out players that much bonus money. This is why you often see these small casino sign up offer deals that then pack a huge punch.

Pros and cons of 400% welcome bonus

Even though big welcome bonuses look good, they do have their own pros and cons. Getting more bang for your buck is a big plus, but with that comes some drawbacks that you need to be aware of.

Here are some of the biggest perks and flaws of 400% bonuses.

✅ Perfect for trying out a casino
✅ Low minimum deposit requirements
✅ Simple bonus concept
✅ Maximises the value of your deposit

❌ Maximum amounts are usually small
❌ Terms can be more difficult
❌ Big bonus percentages are rare

How to claim a 400% deposit bonus

Find a casino site with a 400% bonus from our list

1. Find a 400% casino bonus from our list

Here, we have listed tested and reviewed casinos with a 400% welcome bonus. Take a look at the casino list, see what is available for UK players and pick your favourite.

Read the casino review

2. Read the casino review

After picking a casino, you can read the casino review and see what our seasoned experts thought about the site. Let their experiences on the site help you make a decision.

Go to the casino

3. Go to the casino

On every casino review, there is a big green ‘PLAY HERE' button that takes you straight to the casino. If the bonus is an exclusive special offer, then this button is your way to get that deal.

Register and claim your bonus

4. Sign up and claim your bonus

When you get to the casino, you need to sign up and create a casino account. Just fill in the required information, and you are ready to deposit and claim your bonus. Just make sure you read the bonus terms.


Find 400% casino bonuses

New UK casinos with 400% deposit bonus

New casinos are always interesting and even the most seasoned players will take a look at what the market has to offer every now and then. But, getting a player to join a new casino is not that easy, and bonuses are a good way to draw their attention.

Having a new casino with a 400% deposit bonus is a sure-fire method of getting some eyes on you.

Unfortunately, bonus offers this big are rare and hard to come by. This also means that finding new casino websites that have them is not easy.

Here is a list of the newest casinos on Bojoko that have 400% bonus offers.

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Significant terms and conditions with 400% casino bonuses

Like all other bonus offers, 400% casino bonuses have their own terms and conditions. They are basically the same as with smaller bonuses, but certain numbers might be tweaked a bit differently.

Here are the terms that are especially important:

By knowing these terms, you are ready to handle most of the bonus offers on the market. It is still always good to double check the bonus terms and see what each bonus offer is all about.

Comparison with other deposit bonuses

Deposit bonuses come in all shapes and sizes. It is true that the bigger the bonus percentage is, the rarer they are on the market. Getting a 400% match bonus is not easy, but if you go lower, you will get plenty more options.

Check out some of our other deposit bonus pages and see what offers are available for each.

Deposit bonuses and responsible gambling

Even though deposit bonuses may seem like free money, they are still a casino marketing tool. Their goal is to make the threshold lower for you to deposit. The more money you get from the casino, the likelier it is that you would want to put your own money in.

Bonuses all have terms and the casinos have calculated the point where they make money from these offers. Casinos are a business and their goal is to earn a profit. Bonus offers are not altruistic, but rather a way to get more people in.

Taking a bonus is fine, just as long as you read the terms and know what you are agreeing to.

Gambling is a form of entertainment and should never be seen as a way to earn money or fix financial issues.


A 400% deposit bonus is a promotional casino gift that gives you bonus money in relation to your deposit. You get 400% of your deposit in bonus money to a specified limit.

For example, if you deposit £10, you will get an additional £40 as bonus money.

You can get a 400% welcome bonus by first finding a casino that has such a deal, then signing up and making a deposit to your casino account.

You can find casinos with 400% welcome bonuses here on Bojoko, as we have listed and reviewed them for easy picking.

There are only few casinos that offer 400% casino bonuses. Bonuses as big as these are rare.

You can find a list of casinos that offer 400% bonuses right here on Bojoko.


Find 400% casino bonuses


Ville Saari

Article by:

Ville Saari

Ville is an industry veteran, who has written thousands of gambling-related reviews and articles since 2009. He is an IT engineer with a passion for game and strategy optimisation, and to teach the world to play better.

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