Which Suit to Play First in No-Trump
Work on the suit that needs the most effort first, and keep your sure winners and entries for later.
When you have one suit that runs on its own and another that needs setting up, play the suit that needs work first. Keep the suit that runs by itself, and the entries it gives you, for later.
Why it works
Suits with only top winners can be cashed at any time. Suits that need a high card knocked out need entries and time. If you use up your entries cashing the easy suit first, you may not be able to reach the other suit once it is set up.
A worked example
You are in 3NT. West leads the ♥Q.
Dummy (North): ♠ 6 4 3 ♥ 7 5 2 ♦ K Q J 10 9 ♣ A 4 (10 HCP)
Declarer (South): ♠ A K 5 ♥ A K 4 ♦ 3 2 ♣ K 8 6 5 2 (17 HCP)
Sure tricks: ♠A K, ♥A K, ♣A K: six. Diamonds can give you the rest once the ♦A has gone, but dummy's only outside entry is the ♣A.
Win the ♥A and play diamonds at once. If the defenders hold up the ♦A for two rounds, the ♦K and ♦Q win. Dummy then leads the ♦J and they take the ace. Later you cross to the ♣A to cash the ♦10 and ♦9. That's four diamond tricks and ten in total.
Wrong order: cash the ♣A K first. Now when you play diamonds the defenders hold up the ace twice. You win the ♦K and ♦Q, but they win the ♦A on the third round and dummy has no way back. Two diamond tricks, eight in all: one down.
Four common mistakes
Cashing the suit that runs by itself before setting up the suit that needs work.
Using a vital entry to dummy too early.
Forgetting that defenders can hold up their ace to cut you off.
Not counting how many entries the slow suit will need.
When the rule does not apply
If the defence is about to set up their own suit and you have only one stopper left, you may need to cash your tricks rather than give up the lead. Count the defenders' tricks as well as your own. If two suits both need work, start with the one that needs more lost tricks or more entries.
Key takeaways
Set up the slow suit first.
Keep the suit that runs by itself, and its entries, for later.
Expect the defenders to hold up their aces.
Count entries before you touch a suit.