Fourth Suit Forcing

Fourth Suit Forcing occurs when a partnership bids all four suits in the first two bidding rounds. The fourth suit bid is artificial with game-invitational values (10+ points). Although some partnerships play it as game-forcing, this description will explain the more flexible "one-round force" approach.

Example auctions:

Opener    1 2

Responder 1 2

Opener    1 1

Responder 1 2

In each auction, the last bid suit is Fourth Suit Forcing, showing game-invitational values or better. It does not necessarily show or deny an actual suit.

Opener's rebids are natural. However, the priorities are:

1. Showing 3-card support for partner's major
2. Rebidding a suit to show extra length
3. Bidding no-trumps with a stopper in the fourth suit
4. Raising the fourth suit with 4 cards in that suit (rare)

If playing Fourth Suit Forcing as a one-round-force (not game-forcing), then opener must make jump bids to show extra values and commit the partnership to game.

1. Showing 3-card support for partner's major

Opener should strive to show 3-card support if partner's FIRST suit was hearts or spades.

			Opener			Responder
			JT3			KQ952
			KQT54			A2
			A			J32
			KJ52			A87
			Opener     1 2 2 (2)			Responder     1 2 (1) 4 (3)

1. Fourth Suit Forcing.
2. Opener shows 3-card support and minimum strength. Note that he could bid 3 with 15-17 points.
3. Responder jumps to game with 14 points.

2. Rebidding a suit to show extra length

Opener can rebid his first suit to show 6-4 shape, or he can rebid his second suit to show 5-5 or longer.

			Opener			Responder
			KQT7			652
			J			AKT98
			KQT985			64
			K2			AT5
			Opener     1 1 2 (2) 3NT (4)			Responder     1 2 (1) 2NT (3) Pass

1. Fourth Suit Forcing.
2. Opener shows his 6-card diamond suit. Note that with a stronger hand (15+ points), he could bid 3 instead.
3. Responder invites game with his balanced hand and club stopper.
4. Opener accepts the game invitation with 14 points.

3. Bidding no-trumps with a stopper in the fourth suit

Opener can rebid no-trumps if he lacks 3-card support for partner's major suit.

			Opener			Responder
			7			KQ942
			AJT94			63
			A95			K63
			KQJ3			AT2
			Opener     1 2 3NT (2)			Responder     1 2 (1) Pass

1. Fourth Suit Forcing.
2. Opener jumps to 3NT with a diamond stopper and 15-17 points.

4. Raising the fourth suit with 4 cards in that suit

This occurs when opener holds a 3-suiter which is short in partner's first-bid suit.

			Opener			Responder
			9			AQ542
			AT84			KJ9
			A975			K43
			KQ63			87
			Opener     1 2 3 (2) Pass			Responder     1 2 (1) 3NT (3)

1. Fourth Suit Forcing.
2. Opener shows a 4-4-4-1 or 5-4-4-0 pattern. Note that he could not have bid hearts at his second turn, because that would have been a reverse promising 17+ points.
3. Responder knows that opener has a 3-suiter, but chooses to bid 3NT with a balanced minimum.

Fourth Suit Forcing is OFF if any of these conditions apply:

• Responder is a passed hand.

• The opponents overcall or make a takeout double.

• The partnership bids all four suits at the 1-level (rare):

  Opener 1 1

  Responder 1 1

  In this auction, responder's 1 bid is natural and forcing for one round. However, it is not Fourth Suit Forcing (i.e. artificial).

• Opener has made a reverse, showing 17+ points:

  Opener 1 2

  Responder 1 3

  In this auction, opener's 2 bid was a reverse (forcing), because he bypassed 2. Therefore, responder's 3 bid is natural.

• Responder makes a jump-shift in the fourth suit. This is a natural bid, not Fourth Suit Forcing:

  Opener 1 2

  Responder 1 3

  Responder is showing a 2-suited hand (at least 5-4).

• Responder makes a 2-over-1 response at his first turn. His second bid (the fourth suit) is natural, not Fourth Suit Forcing:

  Opener 1 2

  Responder 2 2

  Responder is showing a 2-suited hand with longer clubs.

Fourth Suit Forcing should only be used when responder does not have another attractive bid available, such as:

• Rebidding a 6-card suit
• Bidding no-trumps with a stopper in the fourth suit
• Making a delayed 3-card raise of partner's major suit opening bid
• Raising partner's second suit with 4+ card support