Aadd9 Chord on Ukulele
Aadd9 = A – C# – E – B (Root, Major 3rd, Perfect 5th, Major 9th)
Aadd9 keeps A major's full triad intact and stacks a ninth (B, an octave above the second) on top, without adding the flattened seventh that would turn it into a true dominant ninth chord. On ukulele, that means fretting the G string at the second fret, the C string at the first fret, and the A string at the second fret, leaving the E string open — three fingers across the outer frets with the E string ringing untouched in the middle of the voicing.
Add9 chords have become a signature sound of open, chiming pop and singer-songwriter guitar and ukulele writing, because the ninth sits far enough from the root and third that it colors the chord without muddying it the way a tighter cluster would. Aadd9 functions as a brighter substitute for plain A major almost anywhere the plain triad would go — as the I chord in A major, it adds shimmer to a tonic without changing its underlying major identity, and it's a common choice for the final chord of a song precisely because it resolves the harmony while still leaving a slightly open, unfinished color hanging in the air. Unlike a genuine A9 (which would also include the flat seventh, G natural), Aadd9 keeps a clean major-chord foundation, which is part of why it reads as bright and consonant rather than bluesy or jazzy.
Fingerings
Open Position
How to Practice It
This shape asks for the same three fingers as several other A-based chords but in a slightly different combination, so isolate it rather than assuming muscle memory from A major will transfer directly. Place the index finger on the C string's first fret, then the middle finger on the A string's second fret, then the ring finger on the G string's second fret, checking that the open E string rings loud and clear between the two outer fretted strings — it's the note that gives the chord its open character, and a muted E collapses the voicing back toward a plain triad. A useful comparison drill is alternating Aadd9 with plain A major, listening specifically for the extra ring the B note contributes on top.
Common Progressions
- Iadd9 as a brighter I chord (Aadd9 – D – E, in place of plain A)
- I – IVadd9 – V (A – Dadd9 – E)
- vi – IV – Iadd9 – V (F#m – D – Aadd9 – E)
- Aadd9 often closes a song as a brighter substitute for a plain tonic chord.
FAQ
- What's the difference between Aadd9 and A9?
- Aadd9 keeps the full major triad and adds only the ninth (B); A9 also adds the flattened seventh (G natural), giving it a bluesier, more dominant-chord color that Aadd9 doesn't have.
- Why do songwriters like add9 chords?
- The ninth sits far enough above the root and third to color the chord with an open, chiming brightness without disturbing its clear major identity, which is why it's a common choice for chiming, open-sounding pop writing.
- Which string carries the add9's characteristic openness?
- The open E string, left unfretted in the middle of the shape — if it's muted by accident, the chord collapses back toward the sound of plain A major.
- Can Aadd9 substitute for plain A major in a song?
- Yes, almost anywhere — it keeps the same harmonic function as the I chord while adding brightness, making it a popular drop-in replacement, especially for a song's final chord.
Aadd9 on other instruments: Aadd9 on Guitar, Aadd9 on Piano. Related: how chords are built, chord finder.