Also written Badd9, B or B Add 9th
B add 9 is built from B, D♯, F♯, and C♯. This advanced voicing requires a wide stretch across the upper frets.
The same three notes, with a different one in the bass.
B add 9 uses the formula 1, 3, 5, 9. The major 2nd between B and C♯ adds the ninth, while the major 3rd from B to D♯ gives the major quality. Compare it with B major, which lacks the ninth.
B add 9 functions as the tonic in B major, fitting the I–IV–V–I progression: B major–E major–F♯ major–B major. It suits rock, pop, and gospel styles where the ninth adds sparkle. It also works over B major and B 5th chords.
The default voicing places C♯ in the bass, softening the root emphasis. Use this inversion when the bass line needs to connect stepwise or when the root is covered by another instrument.
B add 9 is played at the 8th fret as 9 9 9 8: middle finger on the E string at fret 9, ring finger on the A string at fret 9, pinky finger on the D string at fret 9 and index finger on the G string at fret 8.
Tip — The stretch between the index finger on the 8th fret and the pinky on the 9th fret of the D string is demanding.
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (E) | 9 | 2 | C♯ (9) |
| 3 (A) | 9 | 3 | F♯ (5) |
| 2 (D) | 9 | 4 | B (1) |
| 1 (G) | 8 | 1 | D♯ (3) |
B add 9 includes the ninth, C♯, which B major omits. The added note creates a brighter, more open sound while keeping the major third.
B add 9 is diatonic to C♯ natural minor and A♭ natural minor. In those keys it acts as a borrowed major chord, often for modal interchange.
Practice moving between B add 9 and B major slowly, keeping fingers close to the fretboard. Gradually increase speed while maintaining clean note separation.