Also written B♭7, B♭ or B♭ Dominant 7th
B♭ 7th is built from B♭, D, F, and A♭. The 6th-fret shape mirrors A 7th one fret higher, so the pinky stretch on the A string is the main physical hurdle.
The same three notes, with a different one in the bass.
B♭ 7th uses the formula 1, 3, 5, ♭7. The minor 7th interval between B♭ and A♭ gives the chord its dominant quality, and the diminished 5th between D and A♭ adds tension. Compare it with B♭ major, which omits the ♭7.
B♭ 7th is the V chord in E♭ major, so it appears in progressions like E♭–A♭–B♭–E♭ (I–IV–V–I). Its dominant pull suits blues, jazz, and rock bass lines that resolve to E♭.
The 6th-fret shape has B♭ in the bass and is the most direct voicing. The B♭7/F inversion at the 1st fret puts F in the bass for a smoother transition from E♭ major, while the B♭7/A♭ inversion at the 4th fret leads into E♭ major by step.
B♭ 7th is played at the 6th fret as 6 8 6 7: index finger on the E string at fret 6, pinky finger on the A string at fret 8, middle finger on the D string at fret 6 and ring finger on the G string at fret 7.
Tip — The pinky must reach from the 6th fret to the 8th fret on the A string while the other fingers hold their frets cleanly.
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (E) | 6 | 1 | B♭ (1) |
| 3 (A) | 8 | 4 | F (5) |
| 2 (D) | 6 | 2 | A♭ (♭7) |
| 1 (G) | 7 | 3 | D (3) |
B♭ 7th is played in open position as 1 1 0 1: index finger on the E string at fret 1, middle finger on the A string at fret 1 and ring finger on the G string at fret 1. The D string rings open.
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (E) | 1 | 1 | F (5) |
| 3 (A) | 1 | 2 | B♭ (1) |
| 2 (D) | open | — | D (3) |
| 1 (G) | 1 | 3 | A♭ (♭7) |
B♭ 7th is played at the 12th fret as 13 13 12 13: middle finger on the E string at fret 13, ring finger on the A string at fret 13, index finger on the D string at fret 12 and pinky finger on the G string at fret 13.
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (E) | 13 | 2 | F (5) |
| 3 (A) | 13 | 3 | B♭ (1) |
| 2 (D) | 12 | 1 | D (3) |
| 1 (G) | 13 | 4 | A♭ (♭7) |
B♭ 7th is played at the 3rd fret as 4 5 3 3: barre your index finger across fret 3, middle finger on the E string at fret 4 and ring finger on the A string at fret 5.
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (E) | 4 | 2 | A♭ (♭7) |
| 3 (A) | 5 | 3 | D (3) |
| 2 (D) | 3 | 1 (barre) | F (5) |
| 1 (G) | 3 | 1 (barre) | B♭ (1) |
B♭ 7th is written as B♭7, or Bb7 in ASCII. It is also spelled A♯ in enharmonic notation for the same sounding root.
B♭ 7th adds an A♭ note, the minor 7th, to the B♭ major triad. That A♭ creates a tritone with D, giving B♭ 7th its dominant tension.
B♭ 7th is built on the fifth degree of E♭ major, where it functions as the dominant. The name comes from that dominant function, not from the chord's internal intervals.