B 9th chord on guitar (B9)

Also called or written B9 or B

B 9th is built from B, D♯, F♯, A and C♯. This advanced barre shape at the 6th fret demands a solid index barre and a muted high e string.

6frBD♯AC♯F♯EADGBE
Positions on the neck1 of 5
Practice B 9th chord

How it is built

BRootD♯Major thirdF♯Perfect fifthAMinor seventhC♯Ninth

Formula 1, 3, 5, ♭7, 9

Inversions
  • Root positionB–D♯–F♯–A–C♯B97-6-7-6-7-×
  • First inversionD♯–F♯–A–C♯–BB9/D♯×-6-7-6-7-7
  • Second inversionF♯–A–C♯–B–D♯B9/F♯no shape on this instrument
  • Third inversionA–C♯–B–D♯–F♯B9/A5-4-4-4-4-5
  • Fourth inversionC♯–B–D♯–F♯–AB9/C♯×-4-4-4-4-5

How do you play a B 9th chord on guitar?

B 9th is played at the 6th fret as 7 6 7 6 7 ×: barre your index finger across fret 6, middle finger on the low E string at fret 7, ring finger on the D string at fret 7 and pinky finger on the B string at fret 7. The high e string stays muted.

Full note and interval breakdown
StringFretFingerNote
6 (E)72B (1)
5 (A)61 (barre)D♯ (3)
4 (D)73A (♭7)
3 (G)61 (barre)C♯ (2)
2 (B)74F♯ (5)
1 (e)muted

AdvancedThe index barre must fret the A string and the G string cleanly while the pinky reaches fret 7 on the B string.

7th fret

B 9th is played at the 7th fret as 7 9 7 8 7 9: barre your index finger across fret 7, ring finger on the A string at fret 9, middle finger on the G string at fret 8 and pinky finger on the high e string at fret 9.

Full note and interval breakdown
StringFretFingerNote
6 (E)71 (barre)B (1)
5 (A)93F♯ (5)
4 (D)71 (barre)A (♭7)
3 (G)82D♯ (3)
2 (B)71 (barre)F♯ (5)
1 (e)94C♯ (2)

B9/D♯ inversion · fret 6

B 9th is played at the 6th fret as × 6 7 6 7 7: barre your index finger across fret 6, middle finger on the D string at fret 7, ring finger on the B string at fret 7 and pinky finger on the high e string at fret 7. The low E string stays muted.

Full note and interval breakdown
StringFretFingerNote
6 (E)muted
5 (A)61 (barre)D♯ (3)
4 (D)72A (♭7)
3 (G)61 (barre)C♯ (2)
2 (B)73F♯ (5)
1 (e)74B (1)

B9/D♯ inversion · fret 9

B 9th is played at the 9th fret as 11 9 9 11 10 9: barre your index finger across fret 9, ring finger on the low E string at fret 11, pinky finger on the G string at fret 11 and middle finger on the B string at fret 10.

Full note and interval breakdown
StringFretFingerNote
6 (E)113D♯ (3)
5 (A)91 (barre)F♯ (5)
4 (D)91 (barre)B (1)
3 (G)114F♯ (5)
2 (B)102A (♭7)
1 (e)91 (barre)C♯ (2)

B9/D♯ inversion · fret 11

B 9th is played at the 11th fret as 11 12 11 11 12 11: barre your index finger across fret 11, ring finger on the A string at fret 12 and pinky finger on the B string at fret 12.

Full note and interval breakdown
StringFretFingerNote
6 (E)111 (barre)D♯ (3)
5 (A)123A (♭7)
4 (D)111 (barre)C♯ (2)
3 (G)111 (barre)F♯ (5)
2 (B)124B (1)
1 (e)111 (barre)D♯ (3)

Why it sounds like that

B 9th stacks a B major triad (1, 3, 5) with a minor seventh and a major ninth: 1, 3, 5, ♭7, 9. The ♭7 A and 9 C♯ create a dominant sound. Compare it with B 7th, which omits the ninth.

What goes wrong with B 9th?

  • Letting the index barre sag so the G string buzzes at fret 6.
  • Allowing the high e string to ring open, adding an E that is not in the chord.
  • Placing the ring finger on the G string instead of the D string, losing the fifth.

When to use it

B 9th acts as the dominant in E major, used in progressions like E–A–B–E (I–IV–V–I). It suits blues, rock and jazz-funk. Compare it with B major to hear how the seventh and ninth add tension.

Changing to and from B 9th

  • Move to A 9th by sliding the shape down two frets to the 4th fret.
  • Move to C 9th by sliding the shape up one fret to the 7th fret.

Which voicing to use

The 6th fret and 7th fret voicings both have B in the bass, but the 7th fret version adds the ninth on top. The B9/D♯ inversion places the third in the bass for smoother voice-leading.

Other B chords

Common questions

How is B 9th written?

B 9th is written as B9. The symbol B9 always means a dominant ninth chord with a minor seventh and a major ninth.

What is the difference between B 9th and B add 9?

B 9th includes the minor seventh A, while B add 9 is a B major triad with the ninth C♯ added and no seventh. The add 9 sounds more open and less tense.

Why does the B9/D♯ inversion have a different bass note?

The B9/D♯ inversion places the third, D♯, in the bass instead of the root B. This creates a smoother stepwise bass line when moving between chords in E major.