Jacoby Transfers

Invented by world champion Oswald Jacoby, the Jacoby Transfer is a popular convention that can improve your notrump bidding. To use this convention, you and your partner agree to change the meanings of your 2D and 2H responses after you open 1NT.

Responder uses one of these artificial bids to describe any hand (of any strength) that has a 5-card or longer major suit. His 2D or 2H response shows 5+ cards in the next higher suit -- 2D shows a heart suit, 2H shows a spade suit. It also "transfers" the actual bid of the real suit to the 1NT opener, who is required to bid the suit responder is promising -- a 2D response forces the 1NT opener to bid 2H; a 2H response forces a 2S bid.

The Jacoby transfer saves bidding space and gives responder an easier, more accurate way to show his strength later in the auction. It also makes the 1NT opener declarer, which can be an advantage. A disadvantage is that gives up the ability to sign off in 2D. Summarized here is one of the simplest transfer systems for those who play a 1NT opening of 15-17 points (If you play 16-18, you can adjust responder's recommended point ranges down by 1 point.)

Responder's First Bid

After partner opens 1NT, responder's bids and their meanings are:

2C = Stayman, asking for a 4-card major.

2D = Transfer to 2H, showing 5+ hearts and any strength. The 1NT opener must bid 2H.

2H = Transfer to 2S, showing 5+ spades and any strength. The 1NT opener must bid 2S.

2S = Minor Suit "Stayman", asking partner for a 4-card minor. You can use 2S to show any hand with both minors, but it's most valuable use is by either a very weak hand or a very strong, slam-invitational hand. With intermediate strength and both minors, you'll usually want to play 3NT, so asking about opener's minor-suit length won't be as helpful.
After responder's 2S, the 1NT opener bids 3C or 3D if he has at least a 4-card suit. Responder can then pass with the weak hand or bid on with a strong hand.
If opener has no 4-card minor, he rebids 2NT. Responder can then show a weak hand by bidding 3C (asking partner to pass or "correct" to 3D). To show a stronger, slam-invitational hand, responder can "cuebid" 3H or 3S to show a singleton.

2NT = Invitational to 3NT, showing about 8-9 points with no 4-card or 5-card major.

3C, 3D = Invitational to 3NT, showing 6-8 points and a long, broken suit. Opener accepts if he has "fillers" in your suit, fast outside tricks and/or a maximum opening.

3H, 3S = If you're using Jacoby transfers, you won't need these bids to show a long suit. You can assign special meanings to them -- for example, they might show 5-5 in the majors (3H to show an invitational hand; 3S for a forcing-to-game hand).

Responder's Rebids

If partner opens 1NT, use the Jacoby Transfer with any hand that has a 5+-card major suit. After partner bids your suit, choose a rebid that describes your hand further.
Here are the meanings of your second bids after the auction:

1NT by partner -- 2D (transfer) by you -- 2H by partner -- _____

Pass = Weak hand (0-7 points).
2NT = Invitational to 4H or 3NT, exactly 5 cards in your suit.
3NT = Game values for 4H or 3NT, exactly 5 cards in your suit.
3H = Invitational to 4H, 6 or more cards in your suit.
4H = Game values, 6 or more cards in your suit.
New suit = Forcing to game, showing a second suit.

Opener's Rebids

If responder transfers and then rebids notrump or a new suit, opener must decide whether to play in notrump or in partner's suit. Always choose partner's major if you have 3+-card support. If partner's rebid was invitational, you must also show your strength by choosing the right level. If responder transfers and rebids 2NT (invitational), you should:

Pass with a minimum opening (15 points) and 2-card support for partner's suit.
Bid 3H with 15 points and 3-card support.
Bid 3NT with 16-17 points and 2-card support.
Bid 4H with 16-17 points and 3-card support.

Over 2NT Openings

You can also use transfers after partner opens 2NT (3D to show 5+ hearts, 3H to show 5+ spades). After the transfer, responder can:

Pass with a weak hand (0-4 points);
Raise to 4 of the major with game values (4-5+ points) and a 6+-card suit;
Rebid 3NT with game values and a 5-card suit; or
Bid a new suit to show a strong, two-suited hand.