Practice on Cuebids
Practice judging whether a notrump auction has enough strength and controls to explore slam.
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Systems
Last updated
2026-07-31
What is Gerber?
Gerber is a 4 bid that asks partner for aces. It is most often used after notrump openings or notrump rebids.
The point of Gerber is to preserve 4NT for quantitative invitations in notrump auctions.
Gerber over 1NT
- 4 asks for aces if the partnership plays Gerber in this auction.
Agreement matters
Gerber creates accidents when one player thinks 4 is natural and the other thinks it asks for aces. Define exactly when Gerber applies.
- Many pairs play Gerber only directly over a notrump bid.
- Some pairs play it after any natural notrump bid.
- If clubs could be natural, be careful.
Responses, signoff, and king ask
A common Gerber response scale is 4 for zero or four aces, 4 for one ace, 4 for two aces, and 4NT for three aces. After the ace response, 5 is often used to ask for kings. One established continuation mirrors the ace scale: 5 shows zero or four kings, 5 one, 5 two, and 5NT three. Another separates all five counts: 5 shows zero, 5 one, 5 two, 5NT three, and 6 four. The partnership must agree which king scale applies.
After the ace response, 4NT by the asker is a signoff in most methods when that bid is still available; it is not quantitative and not a further ask. Other non-club bids are also natural signoffs. Reserve the 5 king ask for hands with grand-slam interest once the partnership holds all four aces; it commits the auction past game with no way back.
The important practical question is not only the scale, but whether 4 is Gerber in the exact auction. Many strong notrump auctions leave 4NT available as quantitative, while 4 handles ace asking.
- Use Gerber mostly when the likely final strain is notrump.
- Prefer key-card methods when a trump suit is already agreed.
- Agree whether jumps to 4 after Stayman, transfers, and natural notrump rebids are included.
Signing off after the response
- 4 shows one ace; with two aces missing, the asker stops.
- After a Gerber response, 4NT by the asker is to play in most methods.
Asking for kings
- Holding the other two aces, the asker continues with 5 for kings.
- On the mirrored scale, 5 shows one king.
Gerber examples
Gerber is easiest when it is immediate over a natural notrump bid. Accidents appear when clubs could be natural or when the auction has already agreed a suit.
Immediate Gerber over 1NT
- 4 asks for aces in many notrump methods.
- In the common response scale, 4 shows one ace.
Gerber over 2NT
- 4 can be Gerber after a 2NT opening if agreed.
- In the common response scale, 4 shows two aces.
Quantitative 4NT stays available
- Many pairs play 4NT as quantitative, not ace asking, in direct notrump auctions.
- That is why 4 is useful as the ace ask.
Hands that ask and hands that invite
Responder should use Gerber only when the answer to an ace question will decide the contract. Balanced hands that merely want to invite slam usually belong in quantitative 4NT instead.
Source-of-tricks Gerber hand
- Opposite a 1NT opening, the long diamond source of tricks makes ace count more useful than a quantitative invitation.
- Responder holds two aces and is missing the spade and diamond aces: a zero-ace reply means stop, one leaves only one ace missing and supports small slam, and two permits grand-slam investigation.
Quantitative hand
- This hand is balanced and wants partner to judge maximum versus minimum.
- A quantitative 4NT is often more descriptive than asking for aces.
Common mistakes
- Assuming every 4 bid is Gerber.
- Using Gerber when a trump suit has already been agreed and RKCB would be clearer.
- Forgetting whether 4NT is quantitative in the same auction.
- Asking for kings with 5 while the partnership is still missing an ace.
FAQ
Is Gerber only over notrump?
Many partnerships restrict Gerber to notrump auctions, but the exact scope is an agreement.
Why use Gerber instead of 4NT?
In notrump auctions, 4NT is often useful as a quantitative invitation. Gerber lets 4 ask for aces instead.