Pass Line vs Don't Pass in Craps
Pass line and don't pass compared on the come-out and after a point, including the common bar on 12.
Pass line and don't pass are the two bets that frame a craps round. They are opposites in spirit, and they are not perfect mirrors in the rules. The difference is small, printed, and easy to miss if you only learn the game from the noise at the table. This comparison follows a common US layout. The words on the cloth you are standing at are the ones that count.
The come-out roll
A round begins with a come-out roll, before a point is set. On that roll the pass line wins if the dice show 7 or 11. It loses if the dice show 2, 3, or 12. Any other total, 4, 5, 6, 8, 9, or 10, becomes the point. The round then continues until that point repeats or a 7 appears.
Don't pass takes the other side of the come-out, with one famous exception. It wins if the come-out is 2 or 3. It loses if the come-out is 7 or 11. On a large share of US tables, a come-out 12 is a push for don't pass: the bet neither wins nor loses, which is why the layout says the 12 is barred. Some tables bar the 2 instead and let 12 win for don't pass. The bar is the reason these two bets are not exact opposites. Without it, a player could cover both sides and lock a result. The bar closes that door.
After the point is set
Once a point is marked, the come-out rules step aside. Pass line wins if the point is thrown again before a 7. Don't pass wins if a 7 is thrown before the point. Nothing else ends the round. A 2, 3, 11, or 12 after the point is set is simply another roll. New visitors often import the come-out meanings into this stage and think an 11 still matters. It does not, until the next come-out.
You can place either bet before the come-out. After a point is set, a new pass line bet is usually refused until the next come-out, because the come-out is the moment those contracts are written. Other craps bets exist and use other timing. The vocabulary for the rest of the table is collected in craps terms for first-time watchers.
Odds behind the line
Many tables let you add an odds bet behind a pass or don't pass bet after the point is on. Where that bet is offered, it is paid at the true chance of the point being settled the way you need, rather than at a shortened price. It cannot stand alone. The flat pass or don't pass bet is still required, and that flat bet is the one that carries the house advantage.
A price that matches the chance is a rules fact. It is not a reason to take a seat. The flat bet remains, the session can still run away from a short-run average, and a smaller edge is still an edge. Expected value in plain language is the tool for reading any price against any chance, including this one.
How people talk themselves into a side
Pass line is the sociable side of the table. A 7 on the come-out draws a cheer, and the layout is printed so that bet is the easy one to reach. Don't pass wins on that same 7 once a point is set, which means a don't-pass player is hoping for the roll everyone else is groaning about. Neither social fact changes the dice. A cheer is not a probability. A groan is not a probability.
Choosing don't pass because it "wins when the table loses" is a mood, not a calculation. Choosing pass because the table prefers it is the same kind of mood. The dice total that matters is the one the contract names. If you cannot state, before the roll, which totals help you on this stage of the round, you do not yet know the bet you are making.
A clean way to watch one round
Stand where you can see the puck that marks the point. On the come-out, say which totals would win a pass bet and which would win a don't-pass bet, including the barred number. When the puck turns, switch the list: pass now needs the point, don't pass now needs a 7. Do that for one full round before you worry about any other box on the layout. The rest of the printed bets are optional complications.
Craps is loud, adult, and legal only in some places. Age limits are often 21 in the United States and differ elsewhere. If you play, decide a loss limit before the first come-out and treat a barred 12 as information, not as an insult from the dice.
Frequently asked questions
Does don't pass win on a come-out 12?
On most US tables, no. A come-out 12 is a push for don't pass, often printed as a bar. A minority of tables bar the 2 instead. Read the layout.
Can I bet pass line after the point is already set?
Usually no. The pass line contract is taken on the come-out. After a point is on, you wait for the next come-out to place a new one.
Do pass and don't pass cancel the house edge if I understand both?
No. Understanding the contract lets you name the bet. The price of each flat bet still favors the house, and the bar exists so the two sides are not a locked pair.