As an AI language model, I don’t have real-time data to provide the exact number of active users for online casinos this year. The popularity and user numbers of online casinos can vary over time. However, I can provide you with a list of popular online casinos that have a significant number of active users:
1. Bet365 Casino
2. 888 Casino
3. LeoVegas Casino
4. Casumo Casino
5. Mr Green Casino
6. Bitstarz Casino
7. Royal Panda Casino
8. PlayAmo Casino
9. Spin Casino
10. Jackpot City Casino
Please note that this list is subjective and based on general popularity. It’s always recommended to do thorough research and read reviews before choosing an online casino to ensure it meets your specific requirements and preferences.