As of 2021, the top 10 casinos in the world with the most gaming machines (slot machines) are:
1. WinStar World Casino and Resort – Thackerville, Oklahoma, USA
2. Venetian Macao – Macau, China
3. Rio Casino Resort – Klerksdorp, South Africa
4. Casino Lisboa – Lisbon, Portugal
5. Mohegan Sun – Uncasville, Connecticut, USA
6. Borgata Hotel Casino & Spa – Atlantic City, New Jersey, USA
7. MGM Grand Las Vegas – Las Vegas, Nevada, USA
8. Foxwoods Resort Casino – Ledyard, Connecticut, USA
9. NagaWorld – Phnom Penh, Cambodia
10. Resorts World Genting – Genting Highlands, Malaysia
Please note that this information is subject to change as new casinos open, and existing ones may alter their number of gaming machines.