There is no difference whatsoever between Auction Bridge and Contract Bridge except in the scoring. Whereas in Contract Bridge the declarer's tricks count toward game or slam only if he bid for them, in Auction Bridge the declarer's overtricks also count toward game or slam. Auction Bridge scoring is as follows:
Provided the declarer has won at least the number of odd-tricks named in his contract, the declarer's side scores for each odd-trick won:
With no trump 10 20 40 With spades trump 9 18 36 With hearts trump 8 16 32 With diamonds trump 7 14 28 With clubs trump 6 12 24
When a side scores, in one or more hands, 30 points or more for odd tricks, it has won a game and both sides start fresh on the next game. When a side has won two games, it wins the rubber and adds 250 points to its score.
If a doubled contract is fulfilled, the declarer's side scores 50 bonus points plus 50 points for each odd trick in excess of the contract. If a redoubled contract is fulfilled, the declarer's side scores 100 bonus points plus 100 points for each odd trick in excess of the contract. These bonuses are in addition to the score for odd tricks, but do not count toward game. Undertricks. For every trick by which the declarer falls short of the contract, the opponents score 50 points; if the contract is doubled, 100 points; if it is redoubled, 200 points.
The side that holds the majority of the trump honors (A, K, Q, J, 10), or of the aces at notrump.
A side that wins 12 of the 13 tricks, regardless of the contract, scores 50 points for a small slam. A side that wins all 13 tricks, regardless of the contract, scores 100 points for grand slam.
Points for overtricks, undertricks, honors and slams do not count toward game. Only odd-tricks count toward game, and only when the declarer fulfills the contract.