Skip to content
Back

The Aadd9 chord on guitar, bright and open

Aadd9 is an A major chord with one note added: B, the ninth. Everything that makes A sound like A stays in place, including the C# that makes it major. The B just opens the chord up, the way a window lets light into a room. It is a favorite in acoustic pop and folk intros, and the open shape is within reach as soon as you know A.

Aadd9 chord: notes and shapes at a glance

  • Name: A add nine
  • Symbol: Aadd9
  • Notes: A, C#, E, B

Each shape below is written from the thickest string to the thinnest: a number is the fret, 0 an open string, x a string you do not play. New to this? See how to read chord diagrams.

Shape Frets, low E to high E Notes, low to high What it is for
Aadd9, open x02420 A E B C# E The A chord with B added on the G string. Bright, open, and easy to arpeggiate.
Aadd9, four strings xx7657 A C# E B Root on the D string, B on top. A clean, compact voicing in fifth position.
Aadd9, stretch shape x 12 11 9 12 x A C# E B First finger on G at 9, second on D at 11, third on A at 12, fourth on B at 12. The classic add9 reach, easier at the twelfth fret.
Aadd9, open x 0 2 4 2 0 · · 2 4 1 · fingers
Aadd9, four strings x x 7 6 5 7 · · 3 2 1 4 fingers
Aadd9, stretch shape x 12 11 9 12 x

Read each diagram from the thickest string on the left to the thinnest on the right. A cross means the string is not played, a circle means it rings open.

Aadd9 on the neck: every A, C#, E, B

Standard tuning, frets 0 to 12. The highlighted notes are the notes of Aadd9: any shape you build from them, anywhere on the neck, is still Aadd9.

Fretboard notes
Swipe the fretboard sideways to see every fret.
0
1
2
3
4
5
6
7
8
9
10
11
12
1 - E
E
F
F#
G
G#
A
A#
B
C
C#
D
D#
E
2 - B
B
C
C#
D
D#
E
F
F#
G
G#
A
A#
B
3 - G
G
G#
A
A#
B
C
C#
D
D#
E
F
F#
G
4 - D
D
D#
E
F
F#
G
G#
A
A#
B
C
C#
D
5 - A
A
A#
B
C
C#
D
D#
E
F
F#
G
G#
A
6 - E
E
F
F#
G
G#
A
A#
B
C
C#
D
D#
E

How to play Aadd9: x02420

  1. Second finger on the fourth string (D) at fret 2: E, the fifth.
  2. First finger on the second string (B) at fret 2: C#, the third.
  3. Fourth finger on the third string (G) at fret 4: B, the ninth. This is the reach; keep the wrist relaxed and the thumb low behind the neck.
  4. Open A for the root, open high E on top. Strum from the A string, with the low E silent.

Then play the strings one at a time. The note to check first is C#, on the B string: if it is muffled, the chord loses its major color and starts sounding like Asus2. The B on the G string should ring as an extra brightness, not as a sour note.

The best ear exercise is A, Aadd9, A: x02220, x02420, x02220. The harmony does not move, but the chord breathes on the middle beat.

Aadd9, Asus2 and A9 are three different chords

All three contain B, which is why they get mixed up. What separates them is whether the C# and the G are there.

Chord Notes Open shape What to remember
Aadd9 A, C#, E, B x02420 The full A major chord, plus the ninth.
Asus2 A, B, E x02200 No C#: B replaces the third. Open, undecided.
A9 A, C#, E, G, B x02423 Adds G, the seventh: a dominant chord that pulls to D.

Notice how close the shapes are. x02420 and x02423 differ only on the high E: open for Aadd9, fret 3 (G) for A9.

Progressions with Aadd9

Because Aadd9 keeps the function of A major, it slots in anywhere A does. Work these slowly with the online metronome, keeping the strumming hand steady while the fretting hand adds the color.

Progression Shapes What to listen for
Aadd9, D, E, A x02420, xx0232, 022100, x02220 I, IV, V, I in A, opening on the brighter chord.
Aadd9, E, F#m, D x02420, 022100, 244222, xx0232 The I, V, vi, IV loop. Follow the B as it appears and disappears.
A, Aadd9, Asus4, A x02220, x02420, x02230, x02220 Three colors on one root. Let each chord ring to the end of its bar.

The shapes for D, E, F#m and Asus4 each have their own page.

The ringing version at the seventh fret

There is one more Aadd9 worth knowing, and it cannot be drawn in a four fret diagram because it mixes high frets with open strings: x07600. Open A string, D string at fret 7 (A), G string at fret 6 (C#), then the open B and high E strings.

The open B sits a whole step above the A two strings below it, and that close rub gives the chord a shimmering, almost bell-like sound. Use the third finger at fret 7 and the second at fret 6, and let everything ring. It is a lovely chord to arpeggiate, and a good reason to look past the first five frets.

Frequently asked questions

How do you play Aadd9 on guitar?
Play x02420: second finger on the D string at fret 2, fourth finger on the G string at fret 4, first finger on the B string at fret 2, with the A and high E strings open. Leave the low E silent.
What notes are in an Aadd9 chord?
Four: A, C#, E and B. The A major triad (A, C#, E) plus B, the ninth. There is no seventh.
What is the difference between Aadd9 and Asus2?
The third. Aadd9 keeps C#, so it still sounds clearly major, and adds B. Asus2 drops the C# and puts B in its place, so it sounds open and undecided, neither major nor minor.
What is the difference between Aadd9 and A9?
A9 also contains G, the minor seventh, which makes it a dominant chord that pulls toward D. Aadd9 has no seventh: it is A major with a color added, and it stays put.
Can I play Aadd9 instead of A?
Often, as long as the melody accepts the B. The chord keeps everything A major has, so the harmony does not change, only the color. Use it on chosen moments, an intro or the last bar of a phrase, rather than everywhere.
Yohann Abbou, guitar teacher and founder of Guitar Social Club

Who made this

Guitar Social Club is the work of Yohann Abbou, a guitar teacher in Paris who teaches adults. Every shape on this page is written string by string and checked against standard tuning, and the diagrams are drawn from those same fret numbers. The rest of our free guitar tools, including the chord finder, work the same way.

More about Yohann on his page, and about why Guitar Social Club exists.