B♭ major 7th chord on bass (B♭maj7)

Also called or written B♭maj7 or B♭M7

B♭ major 7th contains B♭, D, F, and A. The 6th-fret shape requires a wide stretch from the index to the pinky.

6frB♭FADEADG
Positions on the neck1 of 5
Practice B♭ major 7th chord

How it is built

B♭RootDMajor thirdFPerfect fifthAMajor seventh

Formula 1, 3, 5, 7

Inversions

How do you play a B♭ major 7th chord on bass?

B♭ major 7th is played at the 6th fret as 6 8 7 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 7 and ring finger on the G string at fret 7.

Full note and interval breakdown
StringFretFingerNote
4 (E)61B♭ (1)
3 (A)84F (5)
2 (D)72A (7)
1 (G)73D (3)

AdvancedThe pinky must reach the 8th fret on the 3rd string while the index stays at the 6th fret, creating a wide span.

B♭maj7/F inversion · 1-0-0-3

B♭ major 7th is played in open position as 1 0 0 3: index finger on the E string at fret 1 and middle finger on the G string at fret 3. The A and D strings ring open.

Full note and interval breakdown
StringFretFingerNote
4 (E)11F (5)
3 (A)openA (7)
2 (D)openD (3)
1 (G)32B♭ (1)

B♭maj7/F inversion · 1-1-0-2

B♭ major 7th is played in open position as 1 1 0 2: 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 2. The D string rings open.

Full note and interval breakdown
StringFretFingerNote
4 (E)11F (5)
3 (A)12B♭ (1)
2 (D)openD (3)
1 (G)23A (7)

B♭maj7/F inversion · 13-13-12-14

B♭ major 7th is played at the 12th fret as 13 13 12 14: 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 14.

Full note and interval breakdown
StringFretFingerNote
4 (E)132F (5)
3 (A)133B♭ (1)
2 (D)121D (3)
1 (G)144A (7)

B♭maj7/A inversion

B♭ major 7th is played at the 3rd fret as 5 5 3 3: ring finger on the E string at fret 5, pinky finger on the A string at fret 5, index finger on the D string at fret 3 and middle finger on the G string at fret 3.

Full note and interval breakdown
StringFretFingerNote
4 (E)53A (7)
3 (A)54D (3)
2 (D)31F (5)
1 (G)32B♭ (1)

Why it sounds like that

B♭ major 7th is built from the 1, 3, 5, and 7 of the B♭ major scale. The major 7th interval from B♭ to A gives the chord its smooth, resolved character. Compare it to B♭ major, which lacks the A and sounds more straightforward.

What goes wrong with B♭ major 7th?

  • Letting the pinky land flat and mute the 2nd string.
  • Pulling the index finger off the 4th string when reaching with the pinky.
  • Striking the 3rd string too softly so the D note is lost.

When to use it

B♭ major 7th functions as the I chord in B♭ major, heard in B♭–E♭–F–B♭, the I–IV–V–I. It fits jazz standards, R&B, and mellow pop. Use it over B♭ major or B♭ 5th.

Changing to and from B♭ major 7th

  • Sliding the shape down one fret to the 5th fret gives A major 7th.
  • From B♭ major 7th, lift the pinky and move the middle and ring fingers to the 6th fret to play B♭ major.

Which voicing to use

The 6th-fret shape keeps B♭ in the bass for a solid root position. The B♭maj7/F inversion at the 1st fret puts F in the bass, making the chord feel lighter. The B♭maj7/A inversion at the 5th fret has the leading tone A in the bass, adding pull toward B♭.

Other B♭ chords

Common questions

How is B♭ major 7th written?

B♭ major 7th is written B♭M7 or B♭maj7. The ASCII root spelling is Bb. It is also spelled A♯ in enharmonic notation for the same sounding root.

What is the hardest part of B♭ major 7th?

The hardest part is stretching the pinky to the 8th fret while keeping the index on the 6th fret. Practice the stretch slowly to build flexibility.

How does B♭ major 7th differ from B♭ major?

B♭ major 7th adds the A, the major 7th, to the B♭ major triad. That note creates a more sophisticated, jazzy sound.

Can B♭ major 7th be played in a lower register?

Yes, the B♭maj7/F inversion at the 1st fret uses open strings and sits lower on the neck. It sounds warmer and is easier to reach.