I would say the best online sportsbooks are:
BetUS sportsbook - Best overall. Great support system, very transparent sportsbook. Lots of betting options. Lots of matches. Low fees. Withdrawals take a day max. Live betting. Mobile app. Welcome bonus of $3000 if you deposit at least $50. Everygame sportsbook - They only accept US and Canada players. They offer 3 x $250 welcome bonus. 24/7 customer support. And the withdrawals are done within a day, never had to wait more. They have a solid selection and nice odds. Bovada sportsbook - They only accept US and Canada players. Great if you want to bet on sports and play in casino as well. Welcome bonus of $250 + existing player bonuses. Bodog sportsbook - Best for Canada. They also only accept Canadian players. Best for NHL of course. Welcome bonus of 100% bonus up to $400 + 50 free spins.I was playing in Bet365 before, but as soon as I tried the sportsbooks above, I understood what I've missed out before. They are not limiting your bets (like Bet365 does), which means you can actually bet high and win BIG.