A suit combination is the set of cards your side holds in one suit, such as ♠AK1093 in one hand and ♠8765 in the other, and the question of how to play that suit for the most tricks or for the tricks you need. The best play depends on the odds of each layout of the missing cards and on your target: the line for five tricks is often not the line for four.
Suit combinations are pure card play, so they are the same for every bidding system. Most of the time they can be solved exactly, which is why they are such good training material.
What a Suit Combination Is
Look at one suit at a time. You know your 8, 9 or 10 cards; the opponents hold the rest. Every way the missing cards can be divided between West and East is a layout. A line of play is a plan: which card to lead, from which hand, and what to do after each card the defenders play.
For each line you can count the layouts where it wins, weighted by how likely each layout is. The line with the highest total is the best line for that target. Experts know the common combinations by heart; everyone else can learn them, a few at a time.
How the Odds Work
The starting point is how the opponents' cards split. These are the a priori odds, before the auction or the play tells you anything:
| Cards missing | Split | Chance |
|---|---|---|
| 2 | 1-1 | 52.0% |
| 2 | 2-0 | 48.0% |
| 3 | 2-1 | 78.0% |
| 3 | 3-0 | 22.0% |
| 4 | 3-1 | 49.7% |
| 4 | 2-2 | 40.7% |
| 4 | 4-0 | 9.6% |
| 5 | 3-2 | 67.8% |
| 5 | 4-1 | 28.3% |
| 5 | 5-0 | 3.9% |
| 6 | 4-2 | 48.4% |
| 6 | 3-3 | 35.5% |
| 6 | 5-1 | 14.5% |
Two details are easy to miss. An even number of cards tends to split unevenly: four cards split 3-1 more often than 2-2. And each split covers several specific layouts: a 3-1 split of four cards has eight specific layouts (four singletons, either opponent), so each one is about 6.2%. Our free suit break calculator gives these numbers for any suit length.
Eight Ever, Nine Never
The best-known rule about suit combinations: missing the queen, finesse with eight cards and play for the drop with nine. With ♠AKJ32 opposite ♠7654, the drop wins all five tricks 53.1% of the time against 51.4% for the finesse. With ♠AKJ104 opposite ♠765, the finesse wins 50.9% against 32.8%. The full story, including the version for kings and when to ignore the rule, is in finesse or drop.
Why the Target Matters
Take ♠AK932 opposite ♠8754, missing the Q, J, 10 and 6:
| Target | Best line | Chance |
|---|---|---|
| Five tricks | Cash the ace and king | 40.7% |
| Four tricks | Lead low toward the AK9 and play the 9 if West plays the 6 | 95.2% |
Cashing the top honors wins all five tricks when the suit splits 2-2. But if you need only four tricks, that line fails when West holds all four missing cards. Leading toward the AK9 and playing the 9 when West plays low handles that layout too: only QJ106 with East beats you. The four-trick line costs you the five-trick chance on some 2-2 layouts, which is the price of insurance. That is a safety play.
So before you touch a suit, decide how many tricks the contract needs from it.
Restricted Choice
Restricted choice explains a play that looks like a coin flip but is not. Hold ♠AK1093 opposite ♠8765, missing the Q, J, 4 and 2. You cash the ace and West drops the queen. Now you can play for West to hold QJ doubleton (cash the king) or singleton queen (finesse the 10 through East).
If West held QJ doubleton, West could have dropped either honor. With a singleton queen, West had no choice. That makes the singleton about twice as likely: counted exactly, the finesse wins about 65% and the drop about 35%. The rule: when an opponent plays an honor that could be from a doubleton of equal honors, assume it was a singleton and finesse.
Rule of ThumbRestricted choice: when an honor falls that could have come from two equal honors, play the player for a singleton and finesse on the next round.
South opens 1♠, West overcalls 2♥, North raises, South bids game. West leads the ♣K.
You are South in 4♠. You have three side losers, so you cannot lose a trump. You cash the ♠A and West drops the ♠Q.
You have a heart loser, a diamond loser and a club loser, so the trumps must produce five tricks. Win the ♣A and cash the ♠A. West drops the queen.
Cross to dummy with a diamond and lead a spade. East plays low. Restricted choice says finesse: play the ♠10. It wins, you draw East's last trump with the king, and you make ten tricks. A double dummy solver confirms ten tricks on this layout. The 2♥ overcall helps too: West has five hearts, so fewer places for spades.
How to Read a Layout
When you study a combination, write it the same way each time:
- Your cards: North first, then South. ♠AK1093 opposite ♠8765.
- The missing cards: list them high to low. Here: Q, J, 4, 2.
- The target: "need five tricks" or "need four".
- Entries: can you lead from either hand as often as you like? If not, the line may change.
Then list the layouts that matter. Most layouts play themselves: the line is decided by a few critical ones, such as the 4-0 split or the singleton honor.
Common Mistakes
- Playing for the maximum when you need less. The top-tricks line is often not the safest line for the contract.
- Leading from the wrong hand. A finesse works only when the card you finesse against sits in front of your tenace.
- Not cashing the right honor first. Cash the honor that keeps your options open against a 4-0 or 5-0 split.
- Ignoring restricted choice. After an honor falls, the odds are not 50-50.
- Forgetting entries. A line that needs three leads from dummy is no line if dummy has one entry.
Play the Two Combinations
You hold ♦AJ10 in dummy and ♦432 in your hand, with plenty of entries. You need two diamond tricks. How do you play?
Your hand:
You hold ♠AK1093 in your hand opposite ♠8765 in dummy and need five tricks. You cash the ace and West drops the jack. East follows low. What next?
Your hand:
BridgeDummy's suit combination puzzles let you play a single suit card by card against the best defense, so you feel the difference between a line that wins 53% and one that wins 51%. Five new Daily Suit Combos arrive every day, with a leaderboard. To see every layout of a holding at once, enter it in the free card combination analyzer: it shows how many tricks each layout gives with perfect guessing, a ceiling on what any real line can do. More reading: the finesse, safety plays, finesse or drop and the endplay.