A straddle bet is an optional (voluntary) blind bet made by a player before receiving his cards. Straddles are only used in games played with blind structures. Straddles are normally not permitted in tournament formats.
The player immediately to the left of the big blind may place a live straddle blind bet. The straddle must be a raise over the big blind. A straddle is a live bet; the player placing the straddle effectively becomes the “bigger blind”. Action begins with the player to the left of the straddle. If action returns to the straddle without a raise, the straddle has the option to raise. The player to the left of a live straddle may re-straddle by placing a blind bet raising the original straddle. 
A Mississippi straddle buys last action before the flop. House rules permitting Mississippi straddles are common in the southern United States. Usually, a Mississippi straddle can be made from any position, although some house rules only permit the button or the player to the right of the button to place a Mississippi straddle. Like a live straddle, a Mississippi straddle must be at least the minimum raise. Action begins with the player to the left of the straddle. If, for example (in a game with $10-$25 blinds), the button puts a live $50 on it, the first player to act would be the small blind, followed by the big blind, and so on. If action gets back to the straddle with no raise, the straddle has the option of raising. The player to the right of a Mississippi straddle may re-straddle by placing a blind bet raising the original straddle. 
A sleeper is a blind raise placed from any position at the table other than under the gun.
Betting limits apply to the amount a player may open or raise, and come in four common forms: no limit, pot limit (the two collectively called big bet best crypto casinos 2022 ), fixed limit, and spread limit.
All such games have a minimum bet as well as the stated maximums, and also commonly a betting unit, which is the smallest denomination in which bets can be made. For example, it is common for games with $20 and $40 betting limits to have a minimum betting unit of $5, so that all bets must be in multiples of $5, to simplify game play. It is also common for some games to have a bring-in that is less than the minimum for other bets. In this case, players may either call the bring-in, or raise to the full amount of a normal bet, called completing the bet.
In a game played with a fixed-limit betting structure, a player chooses only whether to bet or not – the amount is fixed by rule. To enable the possibility of bluffing, the fixed amount generally doubles at some point in the game. This double wager amount is referred to as a big bet.
For example, a four-round game called “20 and 40 limit” (usually written as $20/$40) may specify that each bet in the first two rounds is $20, and that each big bet used in the third and fourth rounds is $40. This amount applies to each raise, not the total amount bet in a round, so a player may bet $20, be raised $20, and then re-raise another $20, for a total bet of $60, in such a game.
Maximum number of raises
Most fixed-limit games will not allow more than a predefined number of raises in a betting round. The maximum number of raises depends on the casino house rules, and is usually posted conspicuously in the card room. Typically, an initial bet plus three raises, or a bet and four raises, are allowed.
Consider this example in a $20/$40 game, with a posted limit of a bet and three raises. During a $20 round with three players, play could proceed as follows:
Player A bets $20.
Player B puts in another bet, raises another $20, making it $40 to play.
Player C puts in a third bet, raising another $20 on that, thus making it $60 to play.
Player A puts in the fourth bet (she is usually said to cap the betting).
Once Player A has made her final bet, Players B and C may only call another two and one bets (respectively); they may not raise again because the betting is capped.
A common exception in this rule practiced in some card rooms is to allow unlimited raising when a pot is played heads up (when only two players are in the hand at the start of the betting round). Usually, this has occurred because all other players have folded, and only two remain. Many card rooms will permit these two players to continue re-raising each other until one player is all in.
Sometimes a fixed-limit game is played as a kill game. Such a game is played with an additional blind, called the kill blind. The kill blind can be posted from any position at the table. The amount posted is typically twice the typical blind for that game. For example, in a $20/$40 game, the large blind is typically $20. If this game were played with a full kill, the kill blind would be $40. It is also common to find a game with a half kill. For example, when the kill is active in $4/$8 game with a half kill, the game is played at a $6/$12 limit. A pot built from this betting structure is known as a kill pot.
In some card rooms, the player with the kill blind acts last after the big blind regardless of where they are seated in relation to the dealer button. For example, in a five-handed game where player E has earned the kill button and player A is the dealer, the order of action is player D, player A, player B (the small blind), player C (the big blind), player E (the kill blind). After the flop, betting returns to normal.
Rules on how the kill is activated vary. Sometimes the kill is activated by the previous pot being over a particular value. One common value is ten times the value of the large bet (in a $20/$40 game, the kill would be active if the previous pot won was greater than $400). The winner of that pot is required to post the kill blind for the next hand. Another common way a kill is activated is when a single player wins two pots in a row, requiring the winner to post a kill blind on the next hand. The kill will typically remain active if the player with the kill blind continues to win consecutive hands. If a player has won the previous hand and splits the pot with another player, that may also activate a kill hand. If a pot is split and neither player has won the previous hand, winning the pot of the next hand does not typically activate a kill hand.
The term kill, when used in this context, should not be confused with killing a hand, which is a term used for a hand that was made a dead hand by action of a game official.
A game played with a spread-limit betting structure allows a player to raise any amount within a specified range.
For example, a game called “one to five limit” allows each bet to be anywhere from $1 to $5 (subject to other betting rules). These limits are typically larger in later rounds of multi-round games. For example, a game might be “one to five, ten on the end”, meaning that early betting rounds allow bets of $1 to $5, and the last betting round allows bets of $1 to $10.
Playing spread-limit requires some care to avoid giving easy tells with one’s choice of bets. Beginners frequently give themselves away by betting high with strong hands and low with weak ones, for instance. It is also harder to force other players out with big bets.
A game played with a pot-limit betting structure allows any player to raise up to an amount equal to the size of the whole pot before the raise.
For example, let us assume that there is $10 in the pot at the start of a betting round. The first player may open the betting for up to $10. If he does in fact open for $10, the next player may raise to $40 (after calling the $10 bet, the total amount of the pot is $30, so he may raise $30). The third player would be entitled to raise to $140 (after calling $40, the pot would contain $100, thus he may raise $100). Any player may also raise less than the maximum so long as the amount of the raise is equal to or greater than any previous bet or raise in the same betting round.
Some pot-limit games make exceptions to the method described above when calculating the maximum raise in the betting round before the flop:
Some structures treat the small blind as if it were the same size of the big blind in computing pot size. In such a structure, a player can open for a maximum of four times the size of the big blind. For example, if the blinds are $5 and $10, a player may open with a raise to $40. (The range of options is to either open with a call of $10, or raise in increments of five dollars to any amount from $20 to $40.) Subsequent players also treat the $5 as if it were $10 in computing the pot size, until the big blind is through acting on the first betting round.
If the action folds all the way around to the small blind, the maximum amount the small blind can raise is also not universally agreed upon. Some games treat the big blind as a “raise” of the small blind for the purpose of calculating the maximum raise—the small blind is allowed to call the big blind, and then make a pot sized raise of twice the big blind, for a total bet of three times the big blind. Other games treat the blinds as dead money for the purpose of calculating the raise, and allow the small blind to make the same size raise as any other player, i.e. a total bet of three times the big blind plus the small blind.
Because of the disparity in methods of calculation, and the fact that the issue is certain to come up often, most major tournaments will announce the amount of the maximum opening raise to all players any time the betting limits are increased.
A game played with a no-limit betting structure allows each player to raise any amount of his stake at any time (subject to the table stakes rules and any other rules about raising).