How can I use online sportsbooks' bonus bets to my advantage?

The Game Room
1

So now that Missouri has legalized sports betting, the sportsbook apps are offering me bonus bets to sign up (the first hit is free, after all). They’re expecting me to play this dumb - like, bet it all on some wild prop or something. I won’t be doing that. I’ll be betting my money and the house’s money on opposite sides of the same game, so regardless of what happens, I win.

Should I bet my money on a proposition that is close to 1:1? Or should I look for something with longer odds? And I assume that it’s safest to bet my own money on the more-likely outcome, and the house’s money on the less-likely outcome, is that correct?

Also, assuming I bet optimally, could I still wind up losing money in this transaction?

FWIW, I banked $20 and the house has matched my $20. I intend to bet it on one of the NFL games on the weekend of Saturday/Sunday, December 6/7th, since my bonus bets will expire on December 8.

2

If I understand you correctly, you put $20 into your account, and the sportsbook then gave you a $20 bonus bet? You haven’t actually made a bet yet? So I’m assuming you actually have to place the $20 bet to receive a $20 bonus bet?

Right now I’m looking at DraftKings, at the Texans/Colts game. Colts are favored by 3.5 points, and the odds are -110 for them to cover. Texans, at +3.5, also have odds of -100 to cover.

If you do as you propose (bet both sides of this spread at -110 odds), you will have zero dollars in your account before the game starts. If your money bet wins, you will have $38.18 in your account (your $20 bucks returned, plus $18.18 in winnings). If your bonus bet wins, you will have $18.18 in your account. So, yes, you could lose money.