Bridge Bidding Basics: How the Auction Works

Bidding in bridge is an auction in which the four players describe their hands using a fixed vocabulary of 35 bids, and it ends by naming the contract: how many tricks one side has committed to win, and which suit is trumps. Everything else in bridge bidding, every system and every convention, exists to make that description more accurate.

By Tracey Bauer

New to the game entirely? Start with How to Play Bridge: The Complete Beginner's Guide, then come back here.

This page is the map. It covers what the auction is, what each bid promises, how you measure a hand, and what the partnership is actually aiming at. Then it points you at the full explainer for every convention we teach, in the order a player usually meets them. Nothing here is behind a paywall.

What the auction actually is

After the cards are dealt, nobody plays a card until the auction is over. The dealer speaks first and the turn moves clockwise. At your turn you make one of four calls:

• Bid. A number from one to seven plus a denomination: a suit, or no trump. 1♥, 2NT, 4♠.
• Pass. You have nothing to add this round. Passing does not end your involvement, and you can bid later.
• Double. Available only over an opponent's bid. At a high level it says you expect to beat that contract. At a low level it usually asks partner to bid, which is a different animal entirely.
• Redouble. Available only over an opponent's double.

Each bid must be higher than the last one. The auction ends when a bid is followed by three passes in a row, and the last bid becomes the contract. If all four players pass at their first turn, the deal is thrown in with no contract.

That is the whole mechanism. The hard part is not the rules of the auction. The hard part is that you get 35 bids to describe 13 cards to a partner you are not allowed to talk to.

What a bid promises

Every contract starts from a base of six tricks, called the book. The number in your bid is how many tricks you promise beyond those six. So 1♥ promises seven tricks with hearts as trumps. 4♠ promises ten. 7NT promises all thirteen with no trump suit at all, which is a grand slam and is as good as it gets.

The denominations rank in a fixed order, lowest to highest: clubs ♣, diamonds ♦, hearts ♥, spades ♠, then no trump. That ranking is why the auction moves the way it does. Over 1♥ you can bid 1♠ or 1NT without going up a level, but a club or a diamond has to climb to the two level. Seven levels times five denominations is the 35 bids you have to work with, and the cheap ones are worth more than the expensive ones.

How you measure your hand

The common language is high card points. Ace 4, king 3, queen 2, jack 1, which puts exactly 40 in the deck. Shape matters too, because a five-card suit and a singleton are worth real tricks that no point count captures, but HCP is the number partners actually exchange.

Two house numbers to hold onto. Open the bidding with 12 or more high card points. Open 1NT with 15 to 17 and a balanced hand, which is the most precisely defined bid in the game and the reason so many conventions are built on top of it.

Here is what that buys you. Partner opens 1NT showing 15 to 17. You hold 10. You can do arithmetic nobody else at the table can see: 15 plus 10 is 25, and 25 is a game hand. That is the whole trick of bidding, and it is available to a beginner on their first night.

What you are aiming at

Three targets, and knowing which one is live changes every bid you make.

• Partscore. Anything below game. Roughly 20 to 24 combined points. You are trying to land somewhere comfortable and stop.
• Game. 3NT (nine tricks), 4♥ or 4♠ (ten), 5♣ or 5♦ (eleven). Around 25 to 26 combined points. Notice the minors need two more tricks than notrump for the same reward, which is why 3NT is so often the right game even when you hold a nine-card minor fit.
• Slam. Twelve tricks at the six level, thirteen at the seven level. Small slam wants about 33 combined points, grand slam about 37, and both want you to know how many aces are missing before you commit.

An auction that finds the right target and stops there beats a clever auction that lands in the wrong contract.

The conventions, and where each one fits

A convention is an agreement that gives a bid an artificial meaning, so it says something the natural bid could not. Both opponents are entitled to know every agreement you play, which is why partnerships write them down. You do not need any of these to start playing. You meet them roughly in this order.

Opening and responding

• Two Over One is a full system rather than a single convention. A new suit at the two level over partner's one-level major opening forces to game, so neither player has to jump to show strength and the auction has room to breathe.
• The Strong 2♣ opening is the one opening with no ceiling: 22 or more points, or about eight playing tricks. It says nothing at all about clubs.
• Mel's Rule of 23 is not a convention but a judgment rule, and it will save you more points than most conventions will: do not bid 2NT in a later round unless your side holds at least 23 high card points.

After a 1NT opening

• Stayman. A 2♣ response asks a question rather than showing clubs: partner, do you hold a four-card major? Opener answers 2♥ or 2♠ with one, 2♦ with neither.
• Jacoby Transfers. A 2♦ response commands opener to bid 2♥, and 2♥ commands 2♠. You show a five-card major and the strong hidden hand becomes declarer, so the opening lead comes around to it rather than through it.
• Smolen picks up where Stayman gives up. After 1NT - 2♣ - 2♦, responder jumps to three of the shorter major to show five in the other one, which keeps the 5-3 fit findable and keeps the strong hand as declarer.

When the opponents bid too

• Takeout Doubles. A low-level double of their opening does not mean you want to defend. It asks partner to pick a suit, and it is the most useful competitive tool a new player can own.
• Negative Doubles. Partner opens, an opponent overcalls, and your natural bid has been stolen. The double shows the suits you can no longer bid.

Bidding a slam

• Blackwood, devised by Easley Blackwood in 1933, asks partner how many aces they hold. This house plays Roman Keycard 1430, which counts the trump king as a fifth keycard and asks about the trump queen as well.

Writing your agreements down

• The convention card is where a partnership records what all of the above means for the two of you. It is also the fastest way to discover you and your partner do not agree.

After the auction ends

The auction is only half the game. Once the contract is set, one side has to bring it home and the other has to stop it.

• Play of the hand covers making a plan before you play to trick one, counting your tricks, and knowing which ones you have to build.
• Defensive signals and carding cover the other side of the table: attitude, count, suit preference, and which one applies when.

Reference

• The bridge glossary defines 50 terms in plain English, so a word you meet mid-auction has somewhere to go.
• Bidding as partnership communication takes the same material from the other direction: what two people have to agree on before they sit down.

How to actually get better at bidding

Reading about bidding is worth something. Bidding hands is worth more. Three ways in, in increasing order of commitment.

The 50 Conventions in 50 Days series sends you one convention a day in plain English, which is a low-pressure way to meet a lot of them without deciding anything in advance.

The live workshops take one topic at a time with real hands and live questions, and replays are included, so a session you cannot attend is not a session you miss. There is no substitute for asking a question the moment you have it.

The VIP membership bundles the workshop library for players who would rather work through the whole thing than pick one topic at a time.

And whichever route you take: play the hands. Clumsy auctions you learn from beat perfect auctions you copied.

Frequently asked questions

What is bidding in bridge?

Bidding in bridge is an auction in which the four players describe their hands using a fixed vocabulary of 35 bids. It ends by naming the contract: how many tricks one side has committed to win, and which suit is trumps or whether the hand is played in no trump. The auction ends when a bid is followed by three passes in a row.

What does a bridge bid actually promise?

Every contract starts from a base of six tricks, called the book, so the number in a bid is how many tricks you promise beyond those six. A bid of 1♥ promises seven tricks with hearts as trumps, 4♠ promises ten, and 7NT promises all thirteen with no trump suit.

How many points do you need to bid game in bridge?

Around 25 to 26 combined high card points between the two hands is the working number for game. Game is 3NT for nine tricks, 4♥ or 4♠ for ten, or 5♣ or 5♦ for eleven. Because the minor-suit games need two more tricks for the same reward, 3NT is often the better game even with a long minor.

What is the difference between a bid and a convention?

A natural bid means roughly what it says: 1♥ shows hearts. A convention is a partnership agreement that gives a bid an artificial meaning instead, such as a 2♣ response to 1NT asking whether opener holds a four-card major. Conventions let partners exchange information no natural bid could carry, and both opponents are entitled to know every agreement you play.

What order do the suits rank in bridge bidding?

Lowest to highest: clubs ♣, diamonds ♦, hearts ♥, spades ♠, then no trump. That ranking decides how much room a bid costs. Over 1♥ you can bid 1♠ or 1NT at the same level, but a club or diamond bid has to climb to the two level.