No-limit (often abbreviated to just NL) is a type of betting structure for a poker game where the size of all bets and raises in any given betting round is essentially unlimited. No-limit is generally not used as a betting structure for a particular variant that does not have blinds.
No-limit games are usually described with four numbers: the small blind size, the big blind size, the minimum buy-in, and the maximum buy-in. In some cases, players may describe a no-limit game using just one pair of those numbers, such as describing a 2/5 NL game (small and big blind sizes of $2 and $5), or a 100-300 NL game (min and max buy-ins of $100 and $300). The size of the numbers being used to desribe the game usually give the context: while it's conceivable that someone may someday host a NL game with small and big blind sizes of $100 and $300, it's highly unlikely, and people playing at that level undoubtedly know what they mean when they speak to each other about a 100/300 game.
Minimum buy-ins for a NL game are usually in the range of 10-40 times the big blind. Maximum buy-ins vary. Some NL games do not have a maximum buy-in (effectively, "infinite" max buy-in), but all NL games have a minimum buy-in and blind sizes.
In a no-limit game, a player is allowed to bet or raise according to the following rules:
- For the initial bet of any betting round, the player may choose to check, or they may bet an amount no less than the minimum bet at the table. The maximum amount they may bet is the amount of chips they have currently in play on the table.
- If a bet has already been made during a betting round, subsequent players may choose to fold, call, or raise. If a player chooses to raise, the amount of the raise must be no less than the amount of the most recent bet or raise. The maximum amount of their raise is the amount which would cause them to bet all of their remaining chips and go all-in.
Note that each successive betting round in a game "Resets" the betting amounts. The first bettor in a subsequent betting round may choose to bet only the minimum bet again, if they like.
The minimum bet in a no-limit game is usually the amount of the big blind, though some NL games set a specific minimum bet that is larger than the big blind. This is sometimes called the bring-in for the game, or is sometimes called the amount by which a player must enter the pot.
All-in situations can happen in any game that's played for table stakes. However, the most complex situations tend to happen in no-limit and pot-limit games. It's rare to have more than one player all-in at a fixed limit game.
Once a player is all-in, he will contend for the main pot while the remaining players content for one or more side pots as well as the main pot.
A single all-in player is fairly easy to handle. His chips are counted and an equal amount of chips are taken from the stacks of all callers. Those chips are taken into the main pot. All chips leftover after this is done are placed in the side pot - this pot is physically separated from the main pot by the dealer. Any players with chips remaining now continue on with the hand; any chips bet are added to the side pot. At showdown, the players who have been contending for the side pot show their hands and the winner takes the side pot. The all-in player then shows his hand which is compared to the hand already shown by the winner of the side pot. The winner of this showdown takes the main pot.
This get a bit more confusing when multiple players are all-in, but the procedure is basically the same. You always start with the smallest stack and work up to the biggest stacks, creating side pots until you have one or more players with chips remaining. An example will probably make this clearer.
Let's say it's the turn in a no-limit hold'em game and four players are in a hand. Their stacks look like this:
Player 1: $500
Player 2: $400
Player 3: $300
Player 4: $200
There's $200 in the pot from prior betting rounds. On the turn, Player 1 bets $500 and is all-in. The remaining players call. How the money gets in is irrelevant - that all players are all-in is the important point.
The first thing the dealer will do is take $200 (the smallest stack, Player 4) from each player and move that to the main pot. The stacks are now
Player 1: $300
Player 2: $200
Player 3: $100
Player 4: $0
And there is $1,000 in the main pot.
Now the dealer creates side pot #1 by taking $100 (the smallest stack now belongs to Player 3) from each player and setting it apart from the main pot. The stacks are now
Player 1: $200
Player 2: $100
Player 3: $0
Player 4: $0
There is still $1,000 in the main pot.
There is now $300 in side pot #1.
But we're not done because there are still two players with stacks in front of them. The dealer now takes $100 (Player 2's stack) from each player for side pot #2. Player 1 gets his last $100 back.
The river card is dealt and it's time for the showdown. The showdown happens in reverse order starting from the last side pot created. So, in our example, Player 1 and Player 2 turn their hands up. The winner is pushed side pot #2. The winner of that side pot now compares his hand to Player 3 with the winner being pushed side pot #1. Finally, the winner of side pot #1 compares his hand to Player 4 and the winner takes the main pot.
Phew! See, nothing to it.