Most Popular Online Casinos in August · Page 2 of 3

EnergyCasino

Enjoy 30 Free Spins plus a ¥50,000 Welcome Package

Sign-up Bonus:

30

Free Spins

No deposit required

Significant terms: 18+. 30 Free spins (Spins value: $0.10) on Gates of EnergyCasino slot machine available once, to new customers who register at EnergyCasino using the promotional link. Maximum winnings $100. Spins expire after 7 days. · Terms & Conditions apply  ·  Play responsibly

EnergyCasino

Enjoy 30 Free Spins plus a ¥50,000 Welcome Package

  • 30 Free Spins · No deposit required
  • Exclusive No-Deposit Bonus – Available in Japan and Selected Countries only!
  • 100% Bonus up to ¥25,000 with your first deposit (New customers)
  • Bonus available on your second purchase
  • EnergyCasino offers exclusive bonuses for CasinoBonusCenter visitors
  • Japanese players are accepted
  • Play instantly in your browser – No installation required
  • Mobile-friendly games · Enjoy playing on smartphones and tablets
  • Live Casino · Play against real croupiers at EnergyCasino
  • Over $13,807,891 in Jackpots by Games Global
  • Available in multiple languages, including English
  • Tested and certified by Casino Bonus Center · Rating: 4.4/5
  • Popularity: This offer has been claimed by 243 visitors so far this month.
  • 65 Game Providers: Pragmatic Play, NetEnt, NetGaming, Evoplay, Play n GO, Big Time Gaming, Merkur Gaming, NolimitCity, BF Games, Bally Wulff, Just for the Win, Iron Dog Studio, and others.

Rollino

Enter the Fairground with an Exclusive Bonus up to $6,000!

Welcome offer:

200% Bonus up to

$3,000

+ 100 Free Spins

Bonus on first deposit

Terms & Conditions apply ·  Play responsibly

Rollino

Enter the Fairground with an Exclusive Bonus up to $6,000!

  • 200% Bonus up to $3,000 + 100 Free Spins with your first deposit (New customers)
  • Bonus available on your second and third deposit
  • Rollino offers exclusive bonuses for CasinoBonusCenter visitors
  • Japanese players are accepted
  • Play instantly in your browser – No installation required
  • Mobile-friendly games · Enjoy playing on smartphones and tablets
  • Live Casino · Play against real croupiers at Rollino
  • Online sports betting
  • Available in multiple languages, including English
  • Tested and certified by Casino Bonus Center · Rating: 4.1/5
  • Popularity: This offer has been claimed by 226 visitors so far this month.
  • 85 Game Providers: 1X2gaming, Platipus, Red Rake, Spinmatic, VIVO Gaming, High 5, Amatic, Pragmatic Play, Playbro, ThunderSpin, Barbara Bang, Thunderkick, and others.

Merlin Casino

Feel the Spell of Big Wins with Wager-Free Bonuses, Free Spins & Daily Promotions

Sign-up Bonus:

20

Free Spins

No deposit required

Terms & Conditions apply ·  Play responsibly

Merlin Casino

Feel the Spell of Big Wins with Wager-Free Bonuses, Free Spins & Daily Promotions

  • 20 Free Spins · No deposit required
  • Bonus Code: SPINS20
  • 120% Bonus up to $240 + 100 Free Spins with your first deposit (New customers)
  • Bonus available on your second and third deposit
  • Merlin Casino offers exclusive bonuses for CasinoBonusCenter visitors
  • Japanese players are accepted
  • Accepts Bitcoin and other cryptocurrencies
  • Play instantly in your browser – No installation required
  • Mobile-friendly games · Enjoy playing on smartphones and tablets
  • Live Casino · Play against real croupiers at Merlin Casino
  • Online sports betting
  • Available in multiple languages, including English
  • Rating: 3.9/5
  • Popularity: This offer has been claimed by 211 visitors so far this month.
  • 125 Game Providers: Wizard Games, Peter and Sons, Betsolutions, Aviatrix, Yggdrasil Gaming, Eurasian Gaming, Nemesis, SpinLogic, Red Rake, Mr Slotty, UpGaming, Fazi Interactive, and others.

Rich Palms

$35 free chip to try the games and up to $6,000 welcome bonus!

Free Bonus:

$35

No deposit required

Terms & Conditions apply ·  Play responsibly

Explore bonuses at Rich Palms

Rich Palms

$35 free chip to try the games and up to $6,000 welcome bonus!

  • $35 free! No deposit required
  • Bonus Code: PARIS35
  • 300% Bonus up to $3,000 with your first deposit (New customers)
  • Bonus Code: WELCOMEGIFT
  • Bonus available on your second and third deposit
  • Rich Palms offers exclusive bonuses for CasinoBonusCenter visitors
  • Japanese players are accepted
  • Accepts Bitcoin and other cryptocurrencies
  • Play instantly in your browser – No installation required
  • Mobile-friendly games · Enjoy playing on smartphones and tablets
  • Live Casino · Play against real croupiers at Rich Palms
  • Rich Palms is available in English
  • Tested and certified by Casino Bonus Center · Rating: 2.9/5
  • Popularity: This offer has been claimed by 201 visitors so far this month.
  • 12 Game Providers: Fresh Deck, Visionary iGaming, Nucleus Gaming, DragonGaming, SpadeGaming, Rival, BetSoft, Saucify, Betgames.TV, Urgent Games, BGaming, and Dice Lab

Luxury Casino

Receive Exclusive Bonuses up to $1,000 on your first five deposits!

Welcome offer:

100% Bonus up to

$150

Bonus on first deposit

Terms & Conditions apply ·  Play responsibly

Luxury Casino

Receive Exclusive Bonuses up to $1,000 on your first five deposits!

  • 100% Bonus up to $150 with your first deposit (New customers)
  • Bonus available on your second and third deposit
  • Japanese players are accepted
  • Accepts Bitcoin and other cryptocurrencies
  • Play instantly in your browser – No installation required · Optional game downloads available
  • Mobile-friendly games · Enjoy playing on smartphones and tablets
  • Live Casino · Play against real croupiers at Luxury Casino
  • Over $2,208,052 in Progressive Jackpots
  • Available in multiple languages, including English
  • Tested and certified by Casino Bonus Center · Rating: 4.2/5
  • Popularity: This offer has been claimed by 181 visitors so far this month.
  • 39 Game Providers: Infinity Dragon, Evolution Gaming, Real Dealer Studios, Stormcraft, Area Vegas, OnAir Entertainment, Alchemy Gaming, Gold Coin Studios, Neon Valley, Oros Gaming, Half Pixel, Almond Gaming, and others.

Grande Vegas

Get 50 free spins and a welcome package of $300!

Sign-up Bonus:

50

Free Spins

No deposit required

Terms & Conditions apply ·  Play responsibly

Explore bonuses at Grande Vegas

Grande Vegas

Get 50 free spins and a welcome package of $300!

  • 50 Free Spins · No deposit required
  • Bonus Code: 50FREESPINS
  • 150% Bonus up to $300 with your first deposit (New customers)
  • Bonus Code: WELCOME
  • Bonus available on your second purchase
  • Japanese players are accepted
  • Accepts Bitcoin and other cryptocurrencies
  • Play instantly in your browser – No installation required · Optional game downloads available
  • Mobile-friendly games · Enjoy playing on smartphones and tablets
  • Live Casino · Play against real croupiers at Grande Vegas
  • Grande Vegas is available in English
  • Tested and certified by Casino Bonus Center · Rating: 3.2/5
  • Popularity: This offer has been claimed by 167 visitors so far this month.
  • Game Providers: SpinLogic and Visionary iGaming

Casino Kingdom

Get 40 chances to become a millionaire for only $1

Sign-up Bonus:

1

Free Spin

No deposit required

Terms & Conditions apply ·  Play responsibly

Casino Kingdom

Get 40 chances to become a millionaire for only $1

  • 1 Free Spin · No deposit required
  • 40 Free Spins with your first deposit (New customers)
  • Bonus available on your second purchase
  • Japanese players are accepted
  • Accepts Bitcoin and other cryptocurrencies
  • Play instantly in your browser – No installation required · Optional game downloads available
  • Mobile-friendly games · Enjoy playing on smartphones and tablets
  • Live Casino · Play against real croupiers at Casino Kingdom
  • Over $2,208,052 in Progressive Jackpots
  • Available in multiple languages, including English
  • Tested and certified by Casino Bonus Center · Rating: 4.1/5
  • Popularity: This offer has been claimed by 165 visitors so far this month.
  • 39 Game Providers: SlingShot, Barstruck, Flip Five Gaming, Gameburger Studios, Coin Machine Gaming, Snowborn Games, PearFiction, Pragmatic Play, All For One, Fortune Factory, Games Global, Buck Stakes, and others.

Top 10 Online Casino Bonuses in Japan (August 2025)

Expert-Rated Real Money Casinos with Top Bonuses

Looking for the best online casinos in Japan? Our expert team has tested and reviewed hundreds of real money gambling sites to bring you the top 10 choices for August 2025. bitStarz, Zodiac Casino, and SnatchCasino lead our rankings, standing out for their extensive selection of high-paying slots, immersive live dealer tables, exclusive bonuses, and lightning-fast payouts.

Browse our expert-ranked list below and claim your exclusive welcome bonuses today!

Online Casinos JapanWelcome Bonus

Claim up to ¥50,000 in Bonuses

Bonus of 100% up to ¥10,000 + 180 Free Spins

80チャンスは億万長者になるために!

80 Free Spins

Casino Fun, Beach Vibes, Gangster Style

Bonus of 225% up to $1,000 + 100 Free Spins

Daily slots tournaments

Bonus of 100% up to $400

$900 Welcome bonus + 110 extra spins!

Bonus of 100% up to $300 + 100 Free Spins

Get a Free Spin on the Wish Wheel

Bonus of 100% up to $1,000

Sportsbook, casino, live casino

Bonus of 100% up to $100 + 50 Free Spins

ジャックポットが当たる150回のチャンスをゲット

150 Free Spins

The best games, all in a safe place

Bonus of 100% up to $200 + 200 Free Spins

30 free spins plus ¥50,000!

Bonus of 100% up to ¥25,000

* Terms & Conditions Apply ·  Play responsibly

With nearly two decades of experience in the industry, CasinoBonusCenter.com has been analyzing and comparing online casinos since 2006. Our dedicated team of professionals has handpicked the most trusted casinos for Japanese players to ensure you get the biggest sign-up bonuses, top-tier games, and the most rewarding loyalty programs.