The comparison
| Table | The main bet | The side bet | Ratio |
|---|---|---|---|
| Blackjack | Played correctly, 0.5153% | Insurance, 6.7961% | 13.2 times |
| Baccarat | Banker, 1.0579% | Pair, 10.3614% | 9.8 times |
| Baccarat | Banker, 1.0579% | Tie, paying 8, 14.3596% | 13.6 times |
| Ultimate Texas Hold'em | Main game (attributed), 2.2000% | Trips, 3.4979% | 1.6 times |
| 3 card poker | Ante and Play, 3.3730% | 6 Card Bonus, 8.5614% | 2.5 times |
| 3 card poker | Ante and Play, 3.3730% | Pair Plus, original table, 2.3167% | cheaper |
| Craps | Pass line, 1.4141% | Free odds, 0.0000% | no edge at all |
Baccarat is the clearest case. The banker bet is one of the cheapest wagers in any casino at 1.0579%, and the pair bet on the same felt costs 10.3614%, which is nearly ten times as much. Two bets, one table, the same dealer, one decision apart.
Exception one: Pair Plus beats its own game
Pair Plus costs 2.3167% on the original pay table. The Ante/Play bet it sits beside costs 3.3730%. The side bet is the cheaper wager on that table, which is the opposite of what the rule predicts, and it is the only case of it in this dataset.
It survives on one condition. Pair Plus pay tables vary, and the common reduction from 4 to 3 on the flush takes the same bet to 7.2760%, which is more than twice the Ante/Play bet. So the exception is not a property of Pair Plus. It is a property of one pay table, and the sign on the felt decides which of the two you are looking at. The third bet on that same layout, the 6 Card Bonus, obeys the rule at 8.5614%.
Exception two: the bet that costs nothing
Free odds in craps carries a house edge of exactly 0.0000%. Not approximately zero. Zero. It is paid at true odds, which makes it the only wager on any casino floor with no edge against it at all.
And it is a side bet in the strictest sense: it cannot be made on its own. You must first place a pass line bet at 1.4141% to earn the right to place it. That is what makes it interesting rather than a loophole. The casino is not giving anything away; it is selling access to a fair bet at the price of an unfair one, and the more you put behind the line the closer your combined cost moves towards zero without ever arriving.
Why the rule holds everywhere else
A main bet has to be attractive enough to bring people to the table, and it competes with every other table on the floor. A side bet competes with nothing. It is offered to someone who has already sat down, already chosen the game, and is being asked a separate question with a bigger number attached to it.
That is also why side bets carry the pay tables described in the jackpot line: the headline prize supplies almost none of the return, because its job is to make the bet look worth taking rather than to pay anybody.
What to take from it
Not "never take a side bet". Take the one that is priced better than the game it sits on, if the pay table in front of you is the good one, and always take free odds if you are playing the pass line at all. Everything else on this page costs between two and thirteen times the main game, and the numbers are printed on the felt for anyone who wants to check them.
Every figure is read from
edges.json at build time rather than typed
into this page, so the argument cannot drift from the dataset it is about.
Insurance is computed by blackjack_math.py for a six-deck
shoe. The two exceptions are asserted before the page is written: if Pair
Plus stopped being cheaper than Ante/Play, or free odds stopped being
exactly zero, the build would fail rather than publish a claim that had
become false. Last computed September 2026.