Opening Bid Decisions: Rule of 20, Borderline Hands, and When NOT to Open

You pick up your cards and see 11 HCP with two five-card suits. Do you open? What about 13 HCP with 4-3-3-3 shape? Or 10 HCP in third seat after two passes?

Opening bid decisions are the first judgment call in every hand. Get it right, and you’ll find good contracts and make life hard for opponents. Get it wrong, and you’ll either miss games or go down in hopeless partscore.

The Standard: 12+ HCP

The basic rule is 12+ high card points to open at the one level. That’s a good guideline, but it’s not gospel. Shape, position, and vulnerability all matter.

With 14 HCP and 4-3-3-3 distribution, you’ve barely got an opening bid. With 11 HCP and 6-5 distribution, you’ve definitely got one. Bridge isn’t just arithmetic.

Rule of 20

The Rule of 20 is a better guideline than just counting HCP. Add your HCP to the length of your two longest suits. If the total is 20 or more, you can open.

Example 1:

♠AQ942
♥3
♦KJ853
♣Q6

You have 11 HCP. Five spades plus five diamonds is 10. That’s 21 total. Open 1♠.

Example 2:

♠KJ4
♥AQ6
♦Q95
♣J842

You have 12 HCP. Four spades plus four clubs is 8. That’s 20 total. This is a minimum opening, and with that flat shape, some players would pass. But it qualifies under Rule of 20.

Example 3:

♠QJ4
♥K63
♦A95
♣J842

You have 11 HCP. Four spades plus four clubs is 8. That’s 19 total. Pass. You don’t have an opening bid.

The Rule of 20 works because distribution creates tricks. Long suits mean you can ruff, run suits, and generate extra tricks beyond just high cards. Flat hands mean you’re stuck with what you’ve got.

Rule of 22 (Alternative)

Some players use Rule of 22, which adds HCP, length of two longest suits, AND the number of quick tricks (A=1, AK=2, KQ in same suit=1, etc.).

If it’s 22+, open. This makes it slightly harder to open with junky 11-counts.

Both rules work. Rule of 20 is more common and simpler. Pick one and stick with it.

Quick Tricks Matter

Two aces are better than one ace and two kings. Quick tricks are defensive tricks you can take immediately.

♠AK643
♥Q72
♦Q85
♣Q6

This is 12 HCP, but only 2 quick tricks (the ♠AK). Open 1♠. It’s a fine hand.

♠QJ643
♥Q72
♦Q85
♣AK

This is also 12 HCP and 2 quick tricks (the ♣AK). Open 1♠, though this hand is worse because your long suit is weak.

♠QJ643
♥Q72
♦KJ5
♣KQ

This is 12 HCP but only 1 quick trick. You’ve got queens and jacks everywhere. Some players pass this. If you open, you need help from partner fast, or you’re going down.

Three quick tricks is a rock-solid opening. Two is fine. One and a half is borderline. Less than one, and you probably shouldn’t open even with 12 HCP.

When to Open Light

Third seat after two passes:

Your side is limited. Partner passed, LHO passed. You’re not likely to miss game. So you can open light to push opponents around or get your lead in if they buy the contract.

♠KQJ94
♥73
♦Q82
♣J65

That’s only 9 HCP. In first or second seat, pass. In third seat? Open 1♠. You want a spade lead if LHO becomes declarer. And if partner has a fit, you’ll compete for partscore.

The key is to have a good suit. Don’t open 1♣ on junk in third seat. Open in a suit you’d want partner to lead.

Favorable vulnerability:

Not vulnerable vs vulnerable, you can stretch. If you open light and go down, it’s cheap. If you push them to the three level, you might get them for -100 or -200.

♠A8643
♥KQ742
♦5
♣Q3

That’s 10 HCP, but 5-5 shape. Not vulnerable in first or second seat? Some aggressive players open 1♠. You’ve got great shape, and even if partner’s broke, you’re not going down much.

I’m not saying you should always do this. But knowing you can is useful.

When NOT to Open

4-3-3-3 with flat honors:

♠KJ4
♥Q63
♦AJ5
♣Q842

This is 12 HCP. Technically an opening. But it’s the worst 12-count imaginable. Flat shape, no aces, scattered honors. Pass this in first or second seat. In third seat, maybe open 1♣ if you’re bored, but it’s not going to create any magic.

11 HCP with bad shape and weak suits:

♠Q642
♥K73
♦QJ5
♣AJ4

You’ve got 11 HCP and nothing going on. No five-card suit, no aces beyond the club ace, no shape. Pass. Rule of 20 says this is 19 (11 HCP + 4 spades + 4 clubs). Not enough.

Three suits with shortness in partner’s likely suit:

This is subtle, but if you’re light and have a hand that’s likely to misfit with partner, think twice.

♠AKJ94
♥6
♦Q8532
♣75

If partner’s got hearts, this hand is gold. If partner’s got clubs, it’s a disaster. You’ve got 11 HCP and 5-5 shape, so you’re probably opening. Just know that you’re gambling on fit.

Fourth seat with a poor hand:

Everyone’s passed. You’ve got 11 HCP and bad shape. Why are you opening? The opponents are also weak. Take the zero and move on.

Fourth-seat opens should have some playing strength. You’re not preempting (everyone’s already limited). You’re not blocking out the opponents (they already passed). You’re just looking for partscore, and if you don’t have a good suit, you’re creating problems for yourself.

Suit Quality and Rebid Problems

Don’t open 1♥ on a terrible four-card suit. You open 1♥, partner responds 1♠, and now what? You rebid 1NT with a balanced hand, or you bid a minor. But if your hearts are J743, partner might expect better.

Classic rebid problem:

♠A4
♥KJ4
♦AQ95
♣J842

You’ve got 13 HCP. Open 1♦. Partner responds 1♠. You rebid 1NT (12-14 HCP, balanced). Easy.

Now compare:

♠A4
♥KJ42
♦AQ95
♣J84

You’ve got 13 HCP. Open 1♦ or 1♥? If you open 1♦ and partner responds 1♠, you rebid 1NT and miss the 4-4 heart fit. If you open 1♥ and partner responds 1♠, you rebid 1NT and show your shape perfectly.

Open 1♥ with four hearts and four diamonds. You can always show the diamonds later.

But don’t open 1♥ on J742. Open 1♦ and accept that you might miss a heart fit. That’s better than lying about your heart quality.

The “Must Open” Hands

Some hands are clear openers even with 10 or 11 HCP:

♠AKJ1094
♥73
♦AQ5
♣82

That’s 13 HCP, but more important, it’s a self-sufficient spade suit. Open 1♠. You’re taking five or six spade tricks even if partner has nothing.

♠AQJ94
♥AK842
♦5
♣73

That’s 12 HCP with 5-5 majors. Open 1♠. This hand has tons of playing strength. You’re probably taking nine or ten tricks in your best fit.

The “Should NOT Open” Hands

And some hands look like openers but aren’t:

♠Q642
♥KJ3
♦QJ5
♣AJ4

That’s 12 HCP. But it’s flat, it’s got no aces beyond the club ace, and your suits are weak. Pass this in first seat. If you open and partner’s got 10 HCP, you’ll struggle to take nine tricks in notrump.

♠J8643
♥K2
♦QJ5
♣AQ4

That’s 11 HCP with a five-card suit. Rule of 20 says it’s 20 (11 + 5 + 4). But your spade suit is trash, and you’ve got scattered values. Pass. If you open 1♠ and partner raises, you’re declaring with a terrible trump suit.

Position and Strategy

First seat: Standard rules apply. Open with 12+ and good shape, or 13+ with any shape.

Second seat: Same as first seat. You’re not limited, partner’s not limited, and game is possible.

Third seat: After two passes, you can stretch. Open light with a good suit. Don’t open with junk.

Fourth seat: Only open if you’ve got playing strength. Otherwise take the zero. There’s no upside to opening with scattered 11 HCP when everyone’s already passed.

When in Doubt

If you’re staring at a borderline hand and you don’t know what to do, ask yourself:

Do I have two quick tricks? If yes, lean toward opening.
Do I have a good five-card suit? If yes, lean toward opening.
Is my shape interesting (5-4, 6-4, 5-5)? If yes, lean toward opening.
Is this hand flat with scattered honors? If yes, lean toward passing.

And remember: in first and second seat, you can pass and wait. In third seat, you’re running out of chances. In fourth seat, everyone’s weak, so be selective.

Mistakes to Avoid

Opening every 12-count: Some 12-counts are terrible. You’re allowed to pass.

Passing every 11-count: Some 11-counts are great. Rule of 20 exists for a reason.

Opening light in first seat vulnerable: That’s asking for trouble. You go down, you lose big, and partner might have had a hand for game.

Not opening in third seat with a good suit: If you’ve got KQJ94 of spades and 9 HCP, open 1♠ in third seat. You want that spade lead.

Why This Matters

Opening bid decisions set the tone for the auction. Open too light, and you’re going down or missing your best spot. Pass too much, and you’re letting opponents steal boards or you’re missing partscores.

Get comfortable with Rule of 20. Trust your quick tricks. Value shape over flat hands. And when in doubt in third seat, open and make life hard for the opponents.

You won’t get every decision right, but if you’re thinking about these factors instead of just counting to 12, you’re ahead of most players.