Not all wins in backgammon are worth the same. Sometimes a player bears off all 15 of their checkers before their opponent and wins one point. But if the opponent has not borne off even a single checker by the end of the game, the result is no longer a normal win. This is called a Gammon, and the value of the win is doubled.
If the loser's situation is even worse and, when the game ends, they still have a checker on the bar or inside the winner's home board, the result is a Backgammon — a win that is normally worth three times a standard win.
So gammon and backgammon are not merely terms used to describe the result of a game. When a game is played for points, with the doubling cube or as part of a match, the possibility of a gammon directly affects a player's decisions.
What Does It Mean to Be Gammoned?
Suppose you and I are playing a game of backgammon. I bear off all 15 of my checkers while you are still collecting your checkers. At this point, one question determines how the game is scored: Have you borne off at least one checker? If the answer is yes, the result is a normal win or Single Game. But if you have not borne off even one checker, you have been gammoned.
Under standard backgammon rules:
Normal win = 1 times the game value
Gammon = 2 times the game value
Backgammon = 3 times the game value
USBGF defines a gammon in exactly the same way: the loser has not borne off any checker when the game ends.
A Simple Example of a Gammon
Suppose the doubling cube is showing 2. This means the current game value is two points. You have not borne off any checkers, and I bear off my final checker. The result is a gammon.
The scoring is simple:
2 × 2 = 4 points
So instead of two points, I receive four points. This is where the real value of a gammon becomes clear. When the doubling cube is in play, it is no longer simply a matter of winning one extra point. A gammon can sometimes create a difference of several points in the match result. USBGF also calculates the value of gammons and backgammons based on the final cube value.
What Is a Backgammon?
Now let's make the situation slightly worse. I bear off all my checkers, while you have not borne off any checkers. In addition, at least one of your checkers:
is on the bar, or
is still inside my home board.
In this situation, the result is no longer simply a gammon; you have been backgammoned. Under the standard scoring system, a backgammon is worth three times the base game value. So if the game is played without a double and has a base value of one point, the winner receives three points. That means:
Normal win = 1
Gammon = 2
Backgammon = 3
The Difference Between Gammon and Backgammon at a Glance
Result
Loser's Situation
Result Value
Normal win
Has borne off at least one checker
1 times
Gammon
Has borne off no checkers
2 times
Backgammon
Has borne off no checkers and still has a checker on the bar or in the winner's home board
3 times
The difference may seem simple, but it is very important in competitive play because that single checker on the bar or inside the opponent's home board can sometimes change the game value from two times to three times.
Exactly Where Is the Line Between Gammon and Backgammon?
One common mistake among beginners is assuming that if the loser still has many checkers on the board, they have automatically been backgammoned. That is not correct. For a backgammon, two conditions must be true at the same time:
The loser has not borne off any checkers.
At least one of their checkers remains on the bar or inside the winner's home board.
For example, if the loser still has all 15 checkers on the board, but none of them are in the opponent's home board or on the bar, the result is a gammon, not a backgammon. Remember this distinction well because it is one of the key differences between the rules for gammons and backgammons.
Why Does a Checker on the Bar Matter?
Suppose I bear off my final checker. You have not borne off any checkers, and one of your checkers is still on the bar. What is the result? Backgammon.
Under the rules, a checker on the bar creates the same condition as a checker being inside the winner's home board. Therefore, the loser's checker does not necessarily have to be sitting in one of the six home-board points; simply remaining on the bar is enough for a backgammon to be recorded.
This is why some endgame positions are more critical than they initially appear. Sometimes bearing a checker off the bar is the difference between losing by two times and losing by three times.
Gammon Matters Before the Game Ends
A gammon is recorded when the game ends, but the gammon probability can affect your decisions much earlier. A player with a strong position does not only ask, "How likely am I to win this game?"
The more professional question is: "If I win, how likely am I to get a gammon?" The other side of the board has a similar consideration. A player whose winning chances have become low may no longer try to turn the entire game around. Their goal may simply be to bear off at least one checker and avoid being gammoned.
USBGF educational resources also discuss concepts such as Gammon Go and Gammon Save as distinct strategic topics. The probability of a gammon or backgammon can even affect decisions about doubling and taking or passing the cube.
Why Is Bearing Off Just One Checker So Important?
Suppose you are almost certain to lose the game. Your opponent has borne off most of their checkers, while you have only just entered the bear-off stage. In such a situation, winning may no longer be a realistic goal, but one very important objective remains:
Bear off just one checker.
As soon as you legally bear off one checker, you can no longer be gammoned. If your opponent finishes the game, the result will be a normal win. USBGF tournament rules also explicitly state that, under normal circumstances, legally bearing off one checker eliminates the possibility of a gammon.
For example, if the cube is showing 4, the difference becomes significant:
Normal loss = 4 points
Gammon = 8 points
Backgammon = 12 points
Now it becomes clear why a seemingly insignificant checker can sometimes create a four- or even eight-point difference.
The Effect of the Doubling Cube on Gammons and Backgammons
The Doubling Cube is one of the most fascinating parts of modern backgammon. It typically displays the numbers 2, 4, 8, 16, 32 and 64 and determines the current value of the game.
If the cube is showing 4:
Normal win = 4 points
Gammon = 8 points
Backgammon = 12 points
If the cube reaches 8, these values become 8, 16 and 24 respectively. The important point is that a gammon or backgammon does not replace the doubling cube; instead, the result multiplier is applied to the current cube value. USBGF explains this same structure in its official doubling cube education.
Why Do Gammons and Backgammons Matter in Match Play?
In Match Play, players compete until one reaches a specified score, such as 5, 7 or 9 points. In such a match, a gammon can be worth as much as two normal wins, while a backgammon normally awards three times the base win value.
For example, in a match to 7 points, if the cube is showing 2 and a player wins by gammon, they receive four points. Such a result can completely change the course of the match.
There is, however, an important point: points beyond those needed to win the match have no additional value. For example, if a player has six points in a seven-point match and the next game has a raw value of four points, the match ends as soon as that player reaches the required score. This is why gammon strategy in a match always depends on the Score, or the current score of both players.
How Does the Crawford Rule Affect the Game?
In Match Play, there is an important rule known as the Crawford Rule. If the match is played to n points and one player reaches n-1, meaning they are only one point away from winning the match, the doubling cube cannot be used in the following game. This game is called the Crawford Game.
For example, in a match to 7 points, if the score is 6-4, the next game is the Crawford Game and the doubling cube is not used. If the match continues after that game, the cube becomes available again. However, gammons and backgammons retain their value. In other words, removing the doubling cube does not eliminate gammon scoring.
What Is the Jacoby Rule?
The Jacoby Rule is mainly used in Money Games and is not used in standard Match Play. Under this rule, until a double has been offered in the game, gammons and backgammons do not have their extra value and count as a normal win. The purpose of this rule is to prevent the leading player from avoiding a double simply to pursue a gammon and keep the game going unnecessarily long.
So when discussing gammon scoring in a Money Game, it is worth first checking whether the game is being played under the Jacoby Rule. This rule is optional and is not part of standard Match Play rules.
Can a Player Claim a Gammon or Backgammon?
In official tournaments, a player cannot simply gather their checkers whenever they feel the result is certain and say, "That was a gammon!" USBGF rules state that, under normal circumstances, the game and match should continue until they are legally concluded. However, in contact-free positions, a valid resignation or claim can be made for a normal win, gammon or backgammon.
This point is particularly important in official tournaments, where accurate result recording and avoiding disputes between players matter. In a friendly game, someone may not be so strict, but if you are learning tournament rules, it is worth understanding this distinction as well.
A Complete Example: Gammon or Backgammon?
Suppose White has borne off all of their checkers and the game ends.
Case One
Black has already borne off one checker.
Result: Normal win
Case Two
Black has borne off no checkers, but all of their checkers have moved out of White's home board and none are on the bar.
Result: Gammon
Case Three
Black has borne off no checkers and still has one checker on the bar.
Result: Backgammon
Case Four
Black has borne off no checkers and still has one checker inside White's home board.
Result: Backgammon
If you understand these four cases well, much of the confusion surrounding the difference between gammon and backgammon disappears.
Summary of the Difference Between Gammon and Backgammon
If we reduce the whole concept to three lines:
The opponent has borne off at least one checker → Normal win
The opponent has borne off no checkers → Gammon
The opponent has borne off no checkers and has a checker on the bar or in your home board → Backgammon
The scoring multipliers are:
1 → 2 → 3
If the doubling cube is active, these multipliers are applied to the current cube value.
Final Thoughts: A Gammon Is More Than Just a Heavy Loss
Gammons and backgammons may appear to be simply three different ways of scoring the outcome of a game, but once you play backgammon more seriously, the picture changes.
Sometimes your position is so strong that instead of simply aiming for a quick win, you should also consider your chances of getting a gammon. At other times, you may have almost no hope of winning and your entire goal is to bear off one checker so that you do not lose by double. Even the decision to take or pass a double is incomplete without considering gammon probability.
These additional layers are what separate backgammon from a simple race to bear off checkers. It is not just about the dice; risk management, the value of each result and the match score are also part of the game.
So the next time someone says, "I got gammoned," do not think only about the fact that they lost the game. The real questions are: Did they bear off any checkers? Did they also have a checker on the bar or in the opponent's home board? The answers to these two questions determine whether the result is a gammon or a backgammon.