Not all casinos publish their RTP figures, and that is especially true when it comes to sites that accept Americans, but as a general rule you can consider that slots games will pay out in the region of 95%. If you find a game that pays less than that you should probably move on.
Given the difficulty in getting actual, verified, payout numbers for many of these games, it is most likely that you won\\\\\\\\\\\\\\\'t know that the payout is much lower than it should be until you have actually played the game, so that advice is mainly redundant.
Even a game that pays out at a high 97% will not turn a bonus into a profit proposition though. The main benefit to playing this type of game is the jackpots that come with them. Some jackpots can be network linked and reach millions of dollars.
Using the bonus money to extend your play time on these games with the hope of hitting a jackpot is the best play here.
I am no expert when it comes to slots games of any type. I am a more traditional gambler sticking to table games with known edges.
Most slots players don\\\\\\\'t need to be told to play for the jackpots, and finding casinos with networked jackpots can pay off hugely.
But that is a high variance strategy, so you will need to plan your bankroll management around that.
One point I would like to make for those players that do their research and take the time to get the latest RTP numbers for their chosen game at their chosen casino; while this does not apply so much to US online casinos, where casinos do publish verified Return to Player numbers for their different games, sometimes you will find a casino that has a verified RTP for slots of over 100%.
That would seem to indicate that playing these games is a guaranteed winning strategy. But let me point out that those numbers even where they are up to date, will always be for the previous month, so the rate that applied the previous month may not, and most likely will not, apply in the current month.
Second, there is a very good chance that it was a big jackpot win that put those numbers into the players favor.
When you take those two factors into consideration you will find that you are back to a situation where the game has a house edge of anywhere between 2.5% and 7.5%. Other than playing for the jackpots, and networked jackpots where available, I do not have a working strategy for Slots games.
As ever, if this is your game of choice, plan to manage your bankroll as tight as possible to ensure that you are playing when the opportunity to hit a jackpot does arise. Hitting that prize with smaller pay lines is better than missing the chance altogether.