The Complete Rulebook: Crawford Rule, Gammons, Cube Ownership, and Edge Cases

The Opening Roll and Determining First Move

To initiate a game, each player rolls a single die. The player rolling the higher number moves first, playing both numbers rolled (their own die and the opponent’s die).

If both players roll the same number (a tie), neither player moves; both dice are re-rolled until distinct numbers appear. Because of this opening procedure, the opening move of a backgammon game can never be a double (e.g. 1-1, 2-2, 6-6). Exactly 15 unordered non-double dice combinations are possible on the opening roll.

Legal Movement: Points, Intermediate Landings, and Both-Dice Mandate

Checkers move forward by the exact pip count indicated on each die. A player may use one die to move one checker and the other die to move a different checker, or use both dice sequentially on a single checker.

Crucial Technical Rule: When moving a single checker using both dice, the move is treated as two distinct, consecutive steps. The intermediate landing point must be open (not blocked by two or more opposing checkers). You cannot jump over a blocked point unless the intermediate touchdown point is legal.

Doubles: Playing Four Movements

When a player rolls matching dice (such as 4-4 or 6-6), they have rolled "doubles". Rolling doubles grants four separate moves of that numerical value instead of two.

The player must play as many of the four numbers as legally possible (all four if possible, three if only three can be played, two if only two, one if only one). If any legal sequence allows playing all four moves, the player must select a sequence that uses all four.

Hitting Blots, Entering from the Bar, and Bar Priority

A single checker on a point is known as a "blot". When an opposing checker lands on a point occupied by an opposing blot, that blot is "hit" and placed onto the central Bar.

Absolute Rule of Bar Priority: Whenever you have one or more checkers on the Bar, you CANNOT move any other checker on the board until ALL checkers on the Bar have re-entered.

A checker enters from the Bar into the opponent’s home board on the point corresponding to the rolled die (e.g. rolling a 3 enters on the opponent’s 3-point, which is your 22-point). If that point is blocked by two or more opposing checkers, the checker cannot enter on that die. If no legal entry points are open, the player’s entire turn is forfeited.

Bearing Off: Exact Numbers, Higher Numbers, and Forced Plays

Once all 15 of your checkers have successfully reached your home board (points 1 through 6), you may commence bearing off (removing checkers from the board).

• Exact Number: If you roll a number corresponding to an occupied point (e.g., rolling a 4 when you have checkers on the 4-point), you may bear off a checker from that point.

• Higher Number Rule: If you roll a number higher than any point currently occupied by your checkers (e.g., you roll a 6, but your highest occupied point is the 4-point), you must bear off a checker from the highest occupied point.

• Lower Number Limitation: If you roll a lower number, you cannot bear off from a higher point. If you roll a 2 and your 2-point is empty, but your 5-point is occupied, you cannot bear off from the 5-point; you must play a legal move forward within your home board (e.g., 5/3).

Win Conditions: Single Wins, Gammons, and Backgammons

The margin of victory determines the scoring multiplier for the game:

1. Single Win (1x Stake): You bear off all 15 checkers while the opponent has borne off at least one checker.

2. Gammon (2x Stake): You bear off all 15 checkers before the opponent has borne off a single checker. This doubles the point value or monetary stake of the game.

3. Backgammon (3x Stake): You bear off all 15 checkers before the opponent has borne off a single checker, AND the opponent still has at least one checker on the Bar or in your home board. This triples the value of the game.

The Doubling Cube: Ownership, Money Play, and Match Play

The doubling cube is marked with powers of two (2, 4, 8, 16, 32, 64). At the start of a game, the cube is centered at 64 (representing a value of 1) and neither player owns it.

Before rolling the dice on their turn, a player who believes they have an advantage may propose a double. The opponent must choose between:

• Pass (Drop): Immediately forfeit the game and concede 1 point (or current stake).

• Take (Accept): Agree to play on at double the current stakes, taking exclusive ownership of the cube.

Once a player takes a double, only they possess the legal right to redouble in the future (recube).

The Crawford Rule and Tournament Procedure

In tournament match play (e.g., playing a match to 7 points), the Crawford Rule is universally enforced (ratified by the World Backgammon Federation and US Backgammon Federation):

When one player reaches a score that leaves them exactly one point away from winning the match (e.g. leading 6-2 in a 7-point match, known as "1-away, 5-away"), the very next game is designated the "Crawford Game".

During the Crawford Game, the doubling cube is completely prohibited from being used. This prevents the trailing player from immediately doubling on roll one to steal multiple points without risk.

If the leader loses the Crawford game, the rule expires, and the doubling cube becomes active once again for all subsequent games (Post-Crawford play).