BTU 1NT
This bidding system has a strong notrump opening that does not contain a 5-card major. We use the BTU continuations after the 1NT opening: Stayman takes care of invitation with 5+ spades.
| 1NT- | BAL 15–17 |
|---|---|
| 2♣! | STAY, Garbage STAY, or INV 5=♠ |
| 2♦! | TRF, 5+♥ |
| 2♥! | TRF, 5+♠ |
| 2♠! | Minor suit Multi/STAY, 6+m or FG 4+♦ 4+♣ |
| 2NT | NAT INV |
| 3♣ | INV, 6+♣, KQxxxx or better, usually 6–7 HCP |
| 3♦ | INV, 6+♦, KQxxxx or better, usually 6–7 HCP |
| 3♥! | INV, 5+♠, 5+♥ |
| 3♠! | Choice of games, 5+♠, 5+♥ |
| 3NT | S/O |
| 4♣! | Gerber BW |
| 4♦! | Texas TRF, 6+♥ |
| 4♥! | Texas TRF, 6+♠ |
| 4♠! | F QUANT |
| 4NT | QUANT INV to 6NT, NF |
| 5NT | QUANT INV to 7NT, F |
BTU QUANT scheme
BTU reuses 4♠ for QUANT. This fills the blank that Gerber and Texas leave. Standard QUANT usually invites the upper 1/2 to 2/3 of the opening range. This 4♠ serves as a narrower QUANT than 4NT or 5NT by only inviting the top 1/3.
| 1NT-4NT- | QUANT INV to 6NT |
|---|---|
| 6NT | S/O, 16–17 HCP |
| 1NT-5NT- | QUANT INV to 7NT |
|---|---|
| 6NT | S/O, 15 HCP |
| 7NT | S/O, 16–17 HCP |
| 1NT-4♠- | F QUANT |
|---|---|
| 4NT | 15–16 HCP |
| 4NT-5NT! | F to a 5-card suit or 6NT |
| 4NT-7♣! | P/C to a 5-card suit or 7NT |
| 6NT | 17 HCP |
Discussion on bidding 5-5 majors
There are 3 ways to bid 5-5 majors in BTU 1NT: 3♥♠ and via transfers. There is more than one version in BTU. I am demonstrating my recommendation here step by step.
There are 4 levels of 5-5 majors: weak, invitational, choice of games, and slam try.
- Weak: transfer to the better major and pass. Give up on the other one.
- Invitational: anything goes except 3♠.
- FG+: anything goes.
Hands around the game level are prone to interference. On the other hand, leaking opener’s shape can be helpful in slam bidding. As a result, I recommend the following bidding structure:
- Invitational: 3♥
- Choice of games: 3♠
- Slam try: 2♥ and then 3♥