Home | Learn | Slam Bidding | Blackwood

Blackwood - 4NT Asking For Aces

Blackwood in bridge is one of the most commonly used bridge conventions and an important slam bidding tool. The Blackwood 4NT convention is used when you are thinking of bidding a slam and want to find out how many aces partner has.

4NT asking for aces

4NT asks partner to show the number of Aces in his or her hand. 4NT is not a bid you would normally make in a natural sequence which makes it easy to remember that something funny is going on!

Notice that the responses start from the lowest available bid. After hearing partner's response you will normally now be in a position to decide whether or not to bid slam.

Blackwood 4NT Asking for Aces in Bridge

This hand has good trumps, honor cards in partner's suit, an excellent side suit in clubs and a singleton. Slam is a definite prospect. But partner has no aces, so slam is hopeless and you have to be content with 5♠ losing the A and the A.

Blackwood 4NT Asking for Aces in Bridge

This time North shows 1 Ace and South bids the slam.

Asking for aces with a void

If you have a void ( no cards in a suit ) then it's likely that asking for aces won't help you. Your void means you have control of that suit anyway and if partner has the ace then it won't be pulling it's weight. Ideally you would like partner's aces to be working together with your honour cards.

Asking for Kings

If your side has all the aces, you might like to know how many kings partner has. You should only ask for kings if you are interested in bidding a grand slam, where you need all 13 tricks. Bidding 5NT promises that no ace is missing.

5NT asking for kings

Interference after Blackwood

If the opposition bid or double after 4NT then you'll need to alter your responses a little.

DOPI - Blackwood when opponents bid

If the opposition bid after 4NT asking for aces then you can use the DOPI responses


ROPI - Blackwood when opponents double

If the opposition double after 4NT asking for aces then you can use the ROPI responses


Slam bidding is more than just asking for aces

For many players it's tempting to launch into Blackwood or some other ace asking convention at the first sight of slam but you'll need more than just aces to make 12 tricks. Blackwood should only be used when you are sure that your combined strength is sufficient.

Blackwood is not for getting into slams that make, it's for staying out of slams that don't make!

More Slam Bidding Conventions

Blackwood is used when the last bid was a suit. It is not used after a notrump bid. In that case, you use Gerber.

Roman Key Card Blackwood is a varitaion of Blackwood that asks for the King of trumps and sometimes the Queen of trumps as well as the four aces.

4NT when partner's last bid was NT is not Blackwood, it's the Quantitative 4NT.


Log in to comment