Contract points

Contract points are awarded for each odd trick bid and made. Their values depend on the suit (or notrump) and whether the contract is doubled or redoubled; they are not affected by vulnerability. Tricks won beyond that necessary to fulfill the contract are referred to as overtricks and their scoring points are accounted for separately because their values are dependent upon declarer's vulnerability.

Overtrick points

When declarer makes overtricks, their score value depends upon the contract denomination, declarer's vulnerability and whether or not the contract is undoubled, doubled or redoubled. In an undoubled contract each overtrick earns the same as in contract points (30 for notrump and major suit contracts, 20 for minor suit contracts); values increase significantly when the contract has been doubled or redoubled, especially when vulnerable.

Slam bonus

Bonuses are awarded for all slam contracts bid and made:

• a small slam, or successful contract to win 12 of 13 tricks, earns a bonus of 500 points if not vulnerable and 750 points if vulnerable;
• a grand slam, or successful contract to win all 13 tricks, earns a bonus of 1000 points if not vulnerable and 1500 points if vulnerable.

Doubled or redoubled bonus

When a doubled or redoubled contract is made, a bonus is awarded to the declaring side. It is colloquially referred to as a bonus for "insult", meaning that the opponents have insulted the pair by suggesting that the declarer will not make the contract.

• 50 points are awarded for a doubled contract made, and
• 100 points are awarded for a redoubled contract made.

In scoring notation, a doubled contract is indicated by an 'X" after the contract (e.g. a contract of four hearts doubled is indicated by 4♥ X); a redoubled contract is indicated by "XX" (e.g. 4♥ XX).

Penalty points

When a contract is defeated, penalty points are awarded to the defending side. The value of the penalty depends on the number of undertricks, whether the declaring side is vulnerable or not vulnerable and whether the contract was undoubled, doubled or redoubled.

Without a double or redouble, every undertrick has a fixed cost of 100 or 50 points. The scores for (re)doubled undertricks are such that after the first vulnerable undertrick, n vulnerable undertricks cost the same as n+1 undertricks when not vulnerable; for example, four undertricks when doubled and not vulnerable cost 800 points (100+200+200+300), the same as three undertricks when doubled and vulnerable (200+300+300).

Rubber bonus

In rubber bridge only, a bonus is awarded at the conclusion of the rubber as follows:

• for a completed rubber, the side which wins the rubber, i.e. is first to win two games, receives a rubber bonus:
  • if the opponents have won no games, i.e. they are not vulnerable, the rubber bonus is 700 points; colloquially known as a 'fast rubber'
  • if the opponents have won one game, i.e. they are vulnerable, the rubber bonus is 500 points; colloquially known as a 'slow rubber'
• for unfinished rubbers:
  • if but one side has won a game, it scores 300 points, and
  • if but one side has a part-score, it scores 100 points.

Honor bonus or honors

In rubber bridge only, a bonus is awarded for any one hand holding four or five of the honors, i.e. an ace, king, queen, jack or ten.

• 100 points are awarded for any one hand holding any four of the five trump suit honors, and
• 150 points are awarded for any one hand holding all five trump suit honors, or all four aces in a notrump contract.

Honors may be declared and scored at any time after the auction but for strategic reasons it is best to do so at the conclusion of play so as not to give the opponents information about the lay of the cards. Honors may be held by any of the four players, including dummy.

Game or part-game bonus

In duplicate bridge only, game and partial-game bonuses are awarded at the conclusion of each deal as follows:

• any partial contract, i.e. one scoring less than 100 contract points, scores a bonus of 50 points, and
• any game contract, i.e. one scoring 100 or more points, scores a game bonus of 300 if not vulnerable and 500 if vulnerable.

Game or part-game bonus (Chicago)

In four-deal bridge (Chicago) only, contract points accumulate toward a game like in rubber bridge, but game bonuses are awarded like in duplicate bridge. A separate part-score bonus is available in the fourth deal only, without accumulation.

• a partial contract bid and made in the last deal, which is not game-finishing, scores a bonus of 100 points, and
• any game contract, i.e. one scoring 100 or more points (possibly in combination of a previously accumulated part-score), scores a game bonus of 300 if not vulnerable and 500 if vulnerable when completed.

The score sheet

Rubber scoring is tallied on a score sheet divided into four parts where each partnership accumulates points either above the line or below the line.

The objective is to win by scoring the most total points in the rubber; the rubber is completed when one side has twice accumulated 100 or more contract points below the line.

Only contract points are recorded below the line; all other points are recorded above the line. Any of the four players may be the recorder, his side being represented in the "We" column and the opponents in the "They" column. In the ensuing examples, South is the recorder (the 'We' on the score sheet).

An example rubber

The following table summarizes the results of a rubber consisting of six deals.

The following panels illustrate the progression of the scoring on the score sheet.

Deal 1: South bids 2NT making 3. Only the contract points (70) are scored below the line; the overtrick points (30) are scored above the line.

Deal 2: West bids and makes 4♥. This scores 120 contract points below the line; since there are no overtricks, no points are scored above the line. The accumulation of 100 or more points below the line constitutes the end of the first game and is signified by the drawing of a horizontal line. Since no part-game or game bonus is awarded in rubber bridge, East-West do not receive an additional game bonus and North-South do not receive any part-game bonus. Furthermore, the part score of 70 by North-South is no longer available for accumulation towards a game by them; the 70 points are said to be "cut off" as signified by the drawing of the horizontal line. Having won a game, East-West are vulnerable for all subsequent deals of the rubber meaning that they are now eligible for a larger rubber bonus if they win a second game before their opponents win one and they are susceptible to increased penalties if they are defeated in a contract.

Deal 3: West bids 5♣ and goes down 2, vulnerable, undoubled. This scores 200 penalty points for North-South above the line.

Deal 4: South bids 4♠ doubled, not vulnerable and makes 5. North-South score 240 contract tricks below the line, 100 overtrick points above the line and 50 points for 'insult' above the line. Accumulating 100 or more points below the line constitutes the end of the second game, signified by the drawing of a horizontal line. Having won a game, North-South are now also vulnerable for all subsequent deals of the rubber.

Deal 5: North bids 3♣ and makes 4 scoring 60 contract points below the line and 20 overtrick points above the line.

Deal 6: East bids and makes 6♦ - a small slam holding all five top honors. This scores a game of 120 contract points and earns a slam bonus of 750 points above the line (East-West being vulnerable). 150 honor points are scored above the line for holding all five honors. Having again accumulated 100 or more points below the line, East-West win a second game; a horizontal line is drawn to end the rubber.

Rubber Bonus: At the conclusion of the rubber, a rubber bonus is awarded. In this case, East-West have won a slow rubber and receive a 500-point rubber bonus above the line.

Total: The scores for each side are totalled and East-West (the 'They' on the score sheet) win the rubber.

Scoring deals

In duplicate scoring, the score for each deal is independent from all others and is a single number resulting from the addition of points awarded in accordance with either of two cases:

• when the contract is successful, the declaring side receives a positive score which is the sum of the following elements, if applicable: (i) contract points, (ii) overtrick points, (iii) a part-game or game bonus, (iv) a bonus for making any doubled or redoubled contract, i.e. for 'insult', and (v) a slam or grand slam bonus; the defending side receives a negative score of the same absolute value.
• when the contract is defeated, the defending side receives a positive score based upon the number of tricks defeated, declarer's vulnerability, and whether undoubled, doubled or redoubled; the declaring side receives a negative score of the same absolute value.

Comparing deals

Scoring of tricks in notrump contracts

In the 1932 Laws of Contract Bridge, notrump tricks bid and made, and undoubled notrump tricks made but not bid, score 30, 40, 30, 40, 30, 40, 30.^{[5]: law 30}

In 1935 this became 40, 30, 30, 30, 30, 30, 30.^{[6]: law 39}

Scoring of undertricks

8-level bids

It has always been the intention of every official set of Laws of Contract Bridge to forbid contracts for more than thirteen tricks. Some versions have stated this more clearly than others, but this intention of the Laws has never changed.

International Match Points

International Match Point scoring was first introduced at the 1938 European Championships in Oslo.^[11] Its purpose is to moderate the disproportionate effect that a very large score differential (or "swing') on just one or two boards could have on the outcome of a contest involving dozens of boards.^[11] The difference in total points scored by each team is converted to International Match Points (IMPs) using a standard table^[2][12] which has sublinear dependencies on differences to reduce the effect of such large swings.^[4]

Originally named European Match Points (EMPs),^{[lower-alpha 2]} the scale provided for a maximum gain of 12 points as shown in the table below. A revised table was adopted for the 1948 European Championships in Copenhagen with a maximum of 15 points. North American players were first introduced to this scoring method at the 1951 Bermuda Bowl match in Naples, Italy.^[4][11]

Further revisions were made in 1961 and again in 1962 by the World Bridge Federation.^[11]