What is Crossbooking in Poker?

Understanding Crossbooking in Poker

Crossbooking works by comparing tournament results between two or more players.

For example, if you and another player agree to crossbook 10% of each other’s action:

• If you win more money than them, they pay you 10% of the difference

• If they win more, you pay them 10% of the difference

This creates an additional layer of competition beyond the actual tournament.

Crossbooking is not part of the official game rules, it’s a private side agreement between players.

How Crossbooking Works

Crossbooking can be structured in different ways depending on the agreement.

The most common format is a percentage-based bet on net winnings.

Example:

• You cash for $5,000

• Your friend cashes for $2,000

• Difference = $3,000

• At 10% crossbook → they owe you $300

Some players crossbook multiple participants, creating a network of side bets across a tournament field.

These agreements are usually made before the tournament begins and are settled afterward.

Why Players Crossbook

Players use crossbooking for several reasons.

Adding Extra Action

Crossbooking increases the stakes without changing the tournament structure. Even if the buy-in is fixed, you now have additional money on the line.

Friendly Competition

It is often used among friends or professionals to create a competitive side challenge during events.

Hedging Risk

In some cases, players use crossbooking to reduce variance. By having a piece of another player’s results, you partially offset your own outcomes.

Strategic Considerations of Crossbooking

Crossbooking does not change how the cards are dealt, but it can influence decision-making.

For example, if you are crossbooked against another player, you may become more aware of their progress in the tournament.

However, you should still make decisions based on optimal strategy rather than emotional reactions to side bets.

It is also important to ensure that crossbooking does not create conflicts of interest or lead to questionable behavior. Poker rules require that all players act independently, even if side bets exist.

Is Crossbooking Allowed in Poker?

Crossbooking is generally allowed as a private agreement between players, but its acceptability depends on the rules of the poker room, casino, or tournament organiser.

Legality vs. Integrity

From a rules perspective, crossbooking is not inherently illegal because it happens outside the game itself. However, poker is built on independent competition, so any agreement that influences in-game decisions can quickly raise integrity concerns.

The Line Between Crossbooking and Collusion

The most important distinction is that crossbooking must not involve collusion. Players must still act independently, making decisions that maximise their own expected value rather than protecting or benefiting another player. Any coordinated play, even indirectly, can be treated as collusion and is strictly prohibited.

No Sharing of Information

Players who crossbook cannot share information about their hands, strategies, or intentions. Even subtle communication can create an unfair advantage and undermine the fairness of the game. This is one of the key areas where otherwise acceptable agreements can become rule violations.

Impact on Decision-Making

A major concern with crossbooking is how it might affect player incentives. For example, if two players are financially linked, they may subconsciously avoid marginal spots against each other or take lines that reduce variance rather than maximise profit. Strong players are expected to remain objective and play every hand independently.

Room and Tournament Policies

Different poker rooms and tournaments may have specific rules regarding staking, crossbooking, or financial agreements between players. In some cases, disclosure may be required, and in others, certain arrangements may be restricted to prevent conflicts of interest.

If crossbooking leads to unfair play or alters how players compete, it becomes a serious issue and may violate poker rules.