If you prefer a casino room offered by a bookie, then Matchbook casino is a good option for you. If you open via an broker, i think accepts portuguese customers. You can ask bet-ibc support.. If I'm not wrong they are online 7/7As far as I know, 888 casinos, Karamba Casino and Prime Slots are the leaders, as they have good bonuses.
Though, i'd prefer a casino room offered by a bookmaker, it'll be easier for me to mentain the account. I'm from Portugal. Besides Maxbet, any suggestions anyone?