A#6 Chord on Ukulele
A#6 = A# – D – F – G (Root, Major 3rd, Perfect 5th, Major 6th)
Stack a sixth degree, G, on top of the Bb major triad and something convenient happens on ukulele: that exact note is already ringing on the open G string, so it costs nothing to add. What's left to fret is smaller than the note count suggests — the middle finger on the C string's second fret, plus a short barre with the index finger across the E and A strings at the first fret — which makes Bb6 one of the friendlier four-note chords in this whole key, purely because one of its voices needs no hand at all.
There's a reason sixth chords became such a fixture at the end of swing-era phrases: the added sixth here, G, is also the root note of Bb's relative minor, so the chord quietly borrows a bit of that minor-key shading while staying unmistakably major throughout. As the I chord in the key of Bb, it lets a progression land without going flat about it, holding onto a sliver of unresolved color even at the moment of resolution. That same G root is shared with Gm7, which is why some arrangers move between the two spellings almost interchangeably on paper, even though naming the chord Bb6 versus Gm7 points a listener's ear toward two different harmonic centers.
Fingerings
Open Position
How to Practice It
With the open G string contributing nothing that needs fingering, the real work is in the two fretted parts: seat the middle finger on the C string's second fret, then lay the index finger's barre across the E and A strings at the first fret, and check that neither fretted note is choking the open G ringing beside them. Chords that mix open and fretted strings often suffer from volume imbalance rather than wrong notes, so listen specifically for whether the open G is getting struck with the same conviction as the firmly fretted pair. Trading this chord for Gm7 and back again by ear is a worthwhile exercise in hearing how nearly identical notes can imply two different roots.
Common Progressions
- I6, a closing color substituting for a plain tonic (Bb6 ending a phrase)
- I – IV – I6 (Bb – Eb – Bb6, adding color to a repeated tonic)
- I6 – ii – V – I (Bb6 – Cm – F7 – Bb)
- Bb6 is sometimes interchanged in voicing with Gm7, its relative-minor-flavored cousin.
FAQ
- Why does Bb6 use an open string when Bb major doesn't?
- The added sixth, G, happens to be exactly the note the ukulele's G string plays open, so that particular note comes free rather than needing a fourth fretted finger the way it would on most other instruments.
- What gives Bb6 its distinctive character?
- Its added sixth, G, is also the root of Bb major's relative minor, so the chord carries a faint minor-key coloring inside a major triad, a sound long associated with swing-era closing chords.
- Is Bb6 the same chord as Gm7?
- They share most of their notes and can sound similar, but they're not identical in function — Bb6 centers the ear on Bb as its root, while Gm7 centers it on G, even when the shapes nearly overlap.
- What's the easiest part of the Bb6 shape to get wrong?
- Balancing the open G string against the two fretted notes — it's easy to strike the open string too lightly compared to the firmly fretted ones, leaving the chord's characteristic sixth underrepresented in the mix.
- Why do sixth chords sound old-fashioned or nostalgic to many listeners?
- Their association with swing-era big band and early jazz recordings runs deep enough in popular listening habits that the sound itself, independent of any particular song, tends to evoke that period even in modern arrangements.
- Would a beginner typically learn Bb6 before or after plain Bb major?
- After — Bb6 assumes comfort with the two-string barre already needed for plain Bb major, and it's usually introduced once a player wants to add color chords to a repertoire built on the simpler triads.
- Does the open G string change how loud Bb6 sounds compared to a fully fretted chord?
- It can, since an open string generally resonates a little longer and louder than a firmly fretted note at a low fret, which is part of why balancing the strum across both types of string matters here.
A#6 on other instruments: A#6 on Guitar, A#6 on Piano. Related: how chords are built, chord finder.