Practice on Cuebids
Start hands where opener has a five-card major and responder has a game-forcing raise.
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Last updated
2026-08-01
What is Jacoby 2NT?
Jacoby 2NT is an artificial 2NT response to a one-level major opening. It shows a game-forcing raise of opener's major, usually with four-card or longer support and roughly opening values or better.
The bid lets responder separate strong raises from weaker limit raises and preemptive raises.
In Swedish usage, the standard game-forcing convention is Stenberg 2NT. The invitational-or-better variant is Invitstenberg 2NT, so the names should not be used interchangeably.
Game-forcing heart raise
- 2NT is artificial and forcing to game.
- Responder promises four or more hearts; some pairs also allow a hand with three strong trumps by agreement.
Opener's responses
After Jacoby 2NT, opener describes a good second suit, shortness, or strength without shortness. The following traditional structure gives a good five-card side suit priority and uses fast arrival: the faster opener reaches game, the less slam interest opener shows.
Modified Jacoby structures may assign different ranges or meanings, so partnerships using a variant should label it explicitly rather than mixing tables.
- Three of a new suit shows a singleton or void when opener has no good five-card side suit to show first.
- Three of the agreed major shows the strongest hand with slam interest and no shortness, about 18+ points in this table.
- 3NT shows an intermediate hand without shortness, about 15-17 points in this table.
- Four of a new suit shows a good five-card side suit and may conceal shortness elsewhere.
- Four of the agreed major shows a minimum opening without shortness, about 12-14 points in this table.
Slam exploration
Jacoby 2NT is useful because it starts below game and confirms the trump fit. That gives the partnership room to exchange shortness and control information before deciding whether to stop in game or investigate slam.
After opener's rebid, responder places the contract. Returning to four of the agreed major is the weakest action, new suits are control bids showing slam interest, and many pairs move on to a key-card ask once the controls look promising.
Common opener structure
In the traditional table, a good five-card side suit takes priority: opener bids four of that suit even though a 5-5 hand must contain a singleton or void elsewhere. Without a good five-card side suit, opener shows shortness at the three level. Failing both, opener describes strength with 3M, 3NT, or 4M.
Some partnerships agree to show shortness first. A strict shortness-first method cannot retain the traditional four-level side-suit meaning unchanged, because every hand with a five-card opening major and a five-card side suit also has shortness. Those pairs must repurpose or omit the four-level calls. Write down the priority rule and every opener rebid after both 1 - 2NT and 1 - 2NT.
- Shortness-showing rebids help responder judge whether side-suit values are working.
- Balanced minimum hands usually want to slow the auction down.
- Hands with extras can cooperate through controls or key-card once the fit is known.
Opener shows club shortness
- After 1 - 2NT, this hand rebids 3 in the traditional structure to show the singleton club.
- There is no good five-card side suit to show first.
Good five-card side suit takes priority
- After 1 - 2NT, the traditional structure rebids 4 to show the good five-card club suit.
- The singleton heart is still present; the 4 rebid does not deny shortness.
Jacoby 2NT example auctions
The auction after Jacoby 2NT is partnership-specific, but every version tries to answer the same questions: does opener have shortness, extras, or a minimum hand that wants to stop in game?
Opener shows club shortness
- In the traditional structure used here, 3 shows a singleton or void in clubs when opener has no good five-card side suit.
- Responder can judge whether club values are wasted or useful.
Opener signs off with a minimum
- In the traditional structure used here, the jump to game shows a minimum opening without shortness.
- Responder normally passes unless holding serious slam interest.
Control bidding after shortness
- Responder hears diamond shortness in the traditional structure and can start showing controls.
- The confirmed spade fit gives both players a clear trump suit.
Responder signs off after 3NT
- In this table 3NT shows an intermediate balanced hand, about 15-17, without shortness.
- With a minimum game force and no extra shape, responder simply returns to the agreed major.
Responder hand examples
Jacoby 2NT works best with game-forcing support and no urgent shortness to show immediately. Splinters and direct game raises cover different hand types.
Balanced game-forcing raise
- After partner opens 1, this hand is a classic Jacoby 2NT raise.
- Responder has four-card support and enough strength to force game.
Better as a splinter
- After partner opens 1, diamond shortness matters more than a balanced raise structure.
- Use the partnership splinter agreement if available.
Common mistakes
- Forgetting that 2NT is artificial after a major opening.
- Using Jacoby 2NT with only three-card support without agreement.
- Failing to define opener's rebids before adding the convention.
- Failing to discuss whether the convention still applies by a passed hand or after interference.
FAQ
Is Jacoby 2NT forcing to game?
Yes, in standard modern usage Jacoby 2NT is a game-forcing major-suit raise.
Can Jacoby 2NT be used after interference?
Usually not in the same way. After a takeout double many pairs switch to Jordan 2NT, showing a limit raise or better, and after an overcall a cuebid of the enemy suit often takes over as the strong raise.
Does Jacoby 2NT apply by a passed hand?
Most partnerships turn it off once responder has passed because the standard game-forcing treatment requires values a passed hand cannot hold. 2NT then reverts to natural or shows a limit raise by agreement.