This is always a difficult question to answer, because their are so many things that need to be considered when trying to find the best offer available over the Internet. One thing is for certain, the best betting offer is one that doesn't require a deposit. A no deposit bonus is the best betting offer because you get to play the games for free and it comes with absolutely no risk to you. You don't have to make a deposit to play.
To find the best betting offer in the form of a no deposit bonus, you'll have to look over the terms and conditions for the bonuses. Every casino has a set of conditions that must be met by the player when redeeming a no deposit bonus. You'll want to find an offer that has low wagering requirements, minimal game restrictions, no max cashout, and one that lets players cash out their winnings without making a deposit.