400% Casino Bonus UK

By Ville Saari. Updated:

Discover the best 400% deposit bonus casinos. Bonus offers come in all shapes and sizes, and here you can find the big ones.

Basically, every casino has a bonus and finding the biggest bonus percentages is a bit difficult in the sea of small bonuses. But that is what Bojoko is for. Our casino lists, filter tools and experts reviews are here to help you find the right casinos.

List of Sites With 400 Casino Bonus - May 2024

Here on Bojoko, you can find all the casino sites with 400% match bonus offers. We have gone through them and let you know what it's like to play on them. We also make sure they are all UK-licensed and safe to play on.

Below, you can see every UK casino we reviewed with a 400% casino bonus.

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  1. 400%/£40
    1st deposit bonus
    Unibet casino review »
    1st deposit bonus 400%/£40
    Wagering requirements 50x (B)
    Forfeitable 1st deposit bonus Yes
    Minimum deposit for bonus £10
    Bonus code -
    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. GambleAware.org.
  2. 300%/£60 + 20 bonus spins
    1st deposit bonus
    Play here »
    New players only, 18+. Minimum deposit: £10. Wagering requirement: 40x. Maximum withdrawal: £250. The bonus will expire in 30 days. Bonus spins will expire in 48 hours. Game weightings apply for wagering. Full and Bonus terms apply. GambleAware.org.

UK casino websites with 400% deposit bonuses

Best 400% First Deposit Bonuses

Are you ready to get your hands on a 400% bonus from the best casino sites? Here, we have highlighted the top 400% casino bonuses.

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 the best casino with a 400% deposit 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 of 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 don't have to decide 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 the casino by checking the Unibet casino review, or hop right on in and claim the bonus.

Play on Unibet »

How We Rate 400% Casino Bonuses

Here at Bojoko, we rate 400% bonuses by evaluating the bonus compared to other offers and by looking at specific key factors. These include maximum bonus, wagering, bonus terms and withdrawal limits.

Our seasoned casino experts have been reviewing casinos and bonuses for years and are very familiar with what is available in the UK.

When testing and reviewing casinos and their bonuses, these are the features we look for:

You can learn more about our casino reviews and what is important by reading our online casino review guidelines.

What Is a 400% Casino Bonus

A 400% casino bonus is a promotion that gives you bonus funds to use at the casino relative to your deposit. The bonus percentage, in this case, 400%, and the maximum bonus listed tell you how much money you can get.

A standard bonus offer is usually 100%, so getting a 400% deposit bonus is a big deal. These offers are rare, and a casino website with such offer not easy to come by.

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

Big bonus percentages often translate to small maximum bonuses. This is why you often see these relatively small casino sign up offer deals that then pack a huge punch.

New UK Casinos With 400% Deposit Bonus

New casinos are always interesting and from time-to-time, fresh ones can offer you as high as 400% bonus. These offers are not easy to come by though and finding new casino websites that have them is not easy.

Check out the list below anyway for some of the newest UK casinos that have 400% deposit bonuses or other very big bonus offers.

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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

Terms and Conditions of 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.

Pros and Cons of 400% Welcome Bonus

Even though big welcome bonuses look good, they do have their own pros and cons. 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

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.

100% Deposit Bonus

A 100% deposit bonus is the most common and straightforward offer at online casinos. It doubles your deposit amount, providing a balanced boost to your bankroll. This type of bonus is ideal for players who prefer a direct and simple approach with friendly terms.

You can discover the best deals on our 100% deposit bonuses page.

200% Deposit Bonus

Moving up the scale, a 200% deposit bonus triples your deposit, offering a more significant boost. While the terms might be slightly heavier, these offers usually have reasonable conditions with some added punch.

You can explore the casinos with 200% deposit bonuses to find a bonus that matches your preferences.

300% Deposit Bonus

A 300% deposit bonus quadruples your deposit amount, providing you with a huge uplift to start with. The casinos offer these generous bonuses mainly for newcomers, and you want to keep an eye out for conversion caps that may limit your winnings.

Our experts have listed the top 300% deposit bonuses to help you. Check out the reviews and details of their terms before choosing your bonus.

500% Deposit Bonus

At the high end of the scale, a 500% bonus offers a massive increase, multiplying your deposit by six. These bonuses are rare and often come with specific conditions but provide the biggest match percentage.

Check out the 500% deposit bonuses page to find deals of this calibre. Remember to evaluate the terms and conditions before your decision.


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 a few casinos that offer 400% casino bonuses, and we recommend Unibet.

Bonuses as big as these are rare, and we are here to help you find them.

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


Find 400% casino bonuses

About the Author

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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