Updated: Feb 25, 2021
Before you read further
This article is merely a guide to bridge scoring for those interested. It is not necessary to know exactly how bridge scoring works to excel at the game. It is necessary, however, to know the approximate score of a contract as that can influence your decision in bidding. Do not be bogged down trying to remember the specifics of scoring (especially for double and redoubled contracts), but rather recognize some common scores through repetition and experience (for instance, 3NT making would give 400 or 600, 6♥ making would give 980 or 1430, etc.). The more unusual scores (think 1NTxx +6) do not need to be memorized as you can resort to the back of the bidding box or a machine. An incomplete list of some of the patterns can be found in the “Tips and Tricks” section at the end of the article.
Basics about scoring
After all 13 tricks are played, the declaring side counts how many tricks they have taken and compares it with the required number indicated by the contract. If the declarer won fewer tricks than required, the contract is said to “go down,” resulting in a negative score for the declaring score and an equivalent positive score for the defending side. Every trick the declaring side falls short of the contract is an undertrick. If the declarer won at least the number of tricks required, the contract is said to have “made,” resulting in a positive score for the declaring score and the equivalent negative score for the defending side. Excess tricks won by the declaring side over the goal are called overtricks. The magnitude of each positive and negative score will be the topic of this article.
The idea of vulnerability is important when it comes to scoring. For each board, one partnership can be either vulnerable or non-vulnerable. As a result, there are 4 possible vulnerabilities for each deal: None, North-South, East-West, or Both. The specific vulnerability depends on the board number and it follows a cycle of 16.
(Fig. 1: The vulnerability of each board number is shown. Notice how vulnerability follows a cycle of 16, with board 1 and 17 the same, 2 and 18, etc.)
Using the bidding box
The easiest way to calculate the score of a contract is to refer to the bidding box since it does not require any memorizations or calculations.
If the contract makes, go pick the card corresponding to the contract and flip to the backside. The rows represent the result of the contract (making, 1 overtrick, 2 overtricks, etc.) The left half (with the Roman numeral I) represents when the declaring side is non-vulnerable, whereas the right half (with the Roman numeral II) represents when the declaring side is vulnerable. Within each half, they are further split into 3 based on if the contract is passed, is doubled, or is redoubled.
(Fig 2: the front side of a 4♥ card in the bidding box)
(Fig 3: the back side of a 4♥ card in the bidding box)
On the other hand, if the contract goes down, you will look at the back of the pass, double, or redouble cards. Again, they are split into left and right halves based on vulnerability—left (black) is non-vulnerable, and right (red) is vulnerable).
(Fig 4: the front side of the pass, double, and redouble cards)
(Fig 5: the back side of the pass card)
Alternatively, you can use online calculators such as https://www.funbridge.com/counting-bridge.
With these methods taken care of, we will talk about how these scores are calculated in the first place.
If the contract makes
There are a few components to the final score when the contract makes. The formula is as follow:
Final points = base score + overtrick score + bonuses
The base score is the score awarded for each trick the contract requires (i.e. the number part of the contract).
The base score is doubled if the contract is doubled, and the base score is quadrupled if the contract is redoubled. If the base score is greater than or equal to 100 (after accounting for the double or redouble), the contract qualifies for a game bonus (explained in the “bonus” section).
There are a few types of bonuses that each contract can qualify for.
Game Bonus: If the base score of a contract is greater than or equal to 100 (taking into account doubles and redoubles, but not overtricks), then a game bonus is applied based on the vulnerability. If the base score of a contract is less than 100, then a part-score bonus of 50 is applied.
Slam Bonus: A slam bonus is awarded for contracts at the 6 or 7 level. All 6-level contracts receive a small slam bonus, while all 7-level contracts receive a grand slam bonus. The magnitude of the slam bonus depends on the vulnerability. Slam bonuses are applied on top of game bonuses.
“For insult” Bonus: A bonus is applied to a made contract that was doubled or redoubled, colloquially known as a “for insult” bonus.
If the contract goes down
If the contract goes down, the calculation of the score is simpler. 3 factors determine the score: 1) was the contract doubled, redoubled, or neither, 2) vulnerability and 3) how many tricks did the contract go down by.
On the back of the pass, the double, and the redouble cards of the bidding box, you can find the scores for each undertrick for both vulnerabilities. The left column is for non-vulnerable contracts and the right column is for vulnerable contracts.
(Fig #: This is the back of a pass card in the bidding box. Note that each undertrick for a non-vulnerable contract is worth 50 points, while each one for a vulnerable contract is worth 100 points)
(Fig #: This is the back of a double card in the bidding box. In the case that the contract is non-vulnerable, -1 is 100, -2 is 300, and each undertrick beyond that is an additional 300 points. In the case that the contract is vulnerable, -1 is 200 and each undertrick beyond that is an additional 300 points)
(Fig #: This is the back of a redouble card in the bidding box. Note that every one of these scores here is just double of the respective scores at the back of the double card)
Tips and Tricks
Here are some tips and tricks that may assist you in quickly calculating the score of a contract:
For undoubled part-scores made, you multiply how many tricks the declarer took (including any overtricks) by 20 (if it is ♣ and ♦) or by 30 (if it is ♥, ♠, or NT) and add 50. If it is a no-trump, add 10 more. See examples 1, 2, and 3.
The scores for undoubled games appear very frequently, so if you have not memorized them yet due to repetition, here are the basics: (See examples 4, 5, and 6)
3NT starts at 400 or 600 points, depending on vulnerability. Add 30 points per overtrick.
4♥ and 4♠ start at 420 or 620 points, depending on vulnerability. Add 30 points per overtrick.
5♣ and 5♦ start at 400 or 600 points, depending on vulnerability. Add 20 points per overtrick.
The scores for slams can be a bit more tricky since they occur less frequently. I like to use certain scores as references and calculate from there (See examples 7, 8, 9, and 10):
For small slam, 6NT making is 990 or 1440 points, depending on vulnerability. From there, subtract 10 to get the score for 6♥ or 6♠ (980 or 1430, depending on vulnerability). Subtract a further 60 to get the score for 6♣ or 6♦ (920 or 1370, depending on vulnerability). This 60 comes from the fact that majors and minors differ by 10 points each trick, resulting in 60 points over 6 tricks.
For grand slam, 7NT making is 1520 or 2220 points, depending on vulnerability. From there, subtract 10 to get the score for 7♥ or 7♠ (1510 or 2210, depending on vulnerability). Subtract a further 70 to get the score for 7♣ or 7♦ (1440 or 2140, depending on vulnerability). This 70 comes from the fact that majors and minors differ by 10 points each trick, resulting in 70 points over 7 tricks.
The scores of undertricks are useful as well (See examples 11, 12, 13, and 14):
If the contract is undoubled, each undertrick is 50 or 100 points, depending on the vulnerability.
If the contract is doubled: if it is non-vulnerable, it goes 100, 300, 500, and increments by 300 after that; if it is vulnerable, it increments by 300 starting at 200.
If the contract is redoubled: calculate the score for it being doubled, then double that.
The scores of made doubled contracts are more difficult to calculate, and it is not necessary to know the exact scores. However, it is important to know whether a doubled or redoubled contract will reach the threshold for a game bonus since that will result in a drastic change in the score. For instance, 3♦x making is 470 or 670 points, while 2♦x making is only 180 points. (See examples 15 and 16)
For doubled contracts, anything above 2NT, 2 of a major, or 3 of a minor will receive a game bonus. Be careful about doubling those contracts