Non-serious 3NT

[awm]

One of my partners is looking for a good rule about when 3NT is non-serious versus when it's an offer to play in notrump. We play 2/1 game force with some extras (notably gazilli).

 

Of course, there are many cases which seem to be obvious; for example in a 2/1 game force auction where a major suit is clearly agreed, 3NT is non-serious. And in the auction 1M-2M-3NT, it's an offer to play. The trickier situations seem to be competitive auctions, like 1♠-(2♥)-3♥ (limit raise or better). Does anyone have a good (and hopefully succinct) rule for this?

[gnasher]

3NT with a major agreed is:

 

Natural when:

- We have a 3-card raise opposite what might be 5332 shape

- We jump to 3NT instead of making a game try

- We just can't have the combined values for a slam.

 

“I want to accept your game try”, when bid by a limited hand opposite an unlimited hand which has just made a game try that might also be a slam try.

 

Non-serious slam try, when both hands are unlimited. When a non-serious 3NT is available, a cue bid below 3NT doesn’t show or deny extras. When 3M is available as well as 3NT, 3M is a serious slam try and 3NT is non-serious.

 

Asking for a cue bid, when the bidder is unlimited and partner is limited.

[cherdanno]

The trickier situations seem to be competitive auctions, like 1♠-(2♥)-3♥ (limit raise or better). Does anyone have a good (and hopefully succinct) rule for this?

I have an easy rule for competitive auctions - 3NT is always a suggestion to play.

[jdonn]

I definitely think your best bet is to specifically define auctions where you want it to be on and let it be natural all other times.

[helene_t]

It obviously doesn't apply when we might only have a 7-card fit, or when our fit is in a minor.

 

Also it doesn't apply when either partner has a narrow range.

[qwery_hi]

It obviously doesn't apply when we might only have a 7-card fit, or when our fit is in a minor.

 

Also it doesn't apply when either partner has a narrow range.

I like 3NT non-serious only on when we have a 4-4 major fit.

[hanp]

I like non-serious only when we have a major suit fit in an uncontested, gameforcing auction.

[fromageGB]

We've started playing the non-serious NT only recently, so we haven't any failures to correct our thinking, but we play it as always non-serious if a major has been directly agreed (as opposed to preference).

 

So 1♠ 2♠ 3NT is non-serious, as the opener could have been a borderline 2♣ open, and would be interested in a slam opposite a suitable fitting 10 count. Similarly the 1♠ (2♥) 3♥ 3NT sequence is clearly slam-possible.

 

It can certainly apply when the other hand might have a narrow range, and now the 3NT implies lack of ability to cue clubs, and wants to hear if partner has it.

 

Gnasher is not far off, but for us the "non-serious 3NT" when hearts are trumps is in fact 3♠, and bypassing this to bid 3NT is a serious cue bid in spades.

[jdonn]

One particular good agreement regardless of anything else is, if you agree a major on the 2 level in a game forcing auction, 3NT is natural if it bypasses the major, if you want to set up (non)serious 3NT then bid 3 of the major on the way.

 

1♠ - 2♣

2♥ - 2♠

3♦ -

3♠ = Still playing spades now your 3NT is (non)serious

3NT = Offer to play