Bidding and conventions

A bridge bidding cheat sheet

The point counts and ranges you need at the table, on one page. Standard American with five-card majors and a strong notrump, which is what most online robots play. A partnership can agree differently.

Counting your hand

  • Ace 4, King 3, Queen 2, Jack 1. There are 40 in the pack; 10 is average.
  • Length points: add 1 for each card over four in a suit. A six-card suit is worth 2 extra.
  • Shortage points (only once you have found a trump fit, and only as the supporting hand): void 5, singleton 3, doubleton 1.
  • Downgrade honours that are alone and likely to be wasted, like a singleton king or a queen-jack doubleton in the opponents' suit.

Opening bids

  • 1♥ / 1♠: 12–21 points, five or more cards in the suit.
  • 1♣ / 1♦: 12–21 points, three or more cards. Open the longer minor; with 4-4 open ♦, with 3-3 open ♣.
  • 1NT: 15–17 points, balanced (no void, no singleton, at most one doubleton).
  • 2NT: 20–21 points, balanced.
  • 2♣: 22+ points, or a hand within a trick of game regardless of points. Artificial and forcing: it says nothing about clubs.
  • 2♦ / 2♥ / 2♠: weak two, 5–10 points, a good six-card suit.
  • Three of a suit is preemptive: 5–10 points, a seven-card suit. Four of a minor shows eight cards. See preempts.

Responding to one of a suit

With fewer than 6 points, pass. Otherwise:

  • 6–9 points: raise partner's major to the two level with three-card support, or bid a new suit at the one level, or bid 1NT with nothing better.
  • 10–12 points (invitational): jump raise to three of the major with support, or bid a new suit at the two level.
  • 13+ points: you're going to game. Bid a new suit (forcing), or use Jacoby 2NT with four-card support for partner's major.
  • A new suit by responder is forcing. Opener must bid again.
  • A response at the two level in a new suit normally promises 10+ (or a game force: see two over one).
  • Bid four-card suits up the line at the one level: with 4-4, bid the cheaper.

Responding to 1NT (15–17)

  • 0–7, balanced: pass.
  • 8–9, balanced: 2NT, inviting game.
  • 10–15, balanced: 3NT.
  • Any hand with a four-card major and game interest: 2♣, Stayman, asking for a four-card major.
  • A five-card major and a weak hand: Jacoby transfer: 2♦ shows hearts, 2♥ shows spades. Opener bids the suit; you pass or raise.

Opener's rebid

Your rebid tells partner which strength band you're in.

  • Minimum (12–15): rebid your suit at the cheapest level, raise partner cheaply, or bid 1NT.
  • Medium (16–18): jump raise partner, jump rebid your own six-card suit, or bid a new suit at a level higher than necessary (a reverse).
  • Maximum (19–21): jump to game, or jump-shift into a new suit.

A reverse means bidding a second suit higher-ranking than the first, so partner must go to the three level to return to your first suit. It promises about 17+ and a longer first suit. Don't do it with a minimum.

When the opponents bid

  • Overcall at the one level: 8–17 points, a good five-card suit.
  • Overcall at the two level: 11–17, a good five- or six-card suit.
  • Takeout double: 12+ points, shortage in their suit, support (three or more) for every unbid suit. It asks partner to bid, and partner must.
  • 1NT overcall: 15–18, balanced, with a stopper in their suit.
  • Responder's double after an overcall is for takeout, not penalties. See negative doubles.

Slam bidding

  • 33 points between the hands is the rough small slam threshold; 37 for a grand.
  • Blackwood: 4NT asks for aces. Responses: 5♣ = 0 or 4, 5♦ = 1, 5♥ = 2, 5♠ = 3.
  • Don't use Blackwood with a void, or with two quick losers in an unbid suit. Counting aces doesn't tell you they're in the right places.

If you remember four things

  1. 12 to open, 25 for game, 33 for slam.
  2. A new suit by responder is forcing. Don't pass it.
  3. Look for an eight-card major fit first, and fall back on notrump if there isn't one.
  4. Your rebid's job is to show your strength band.