The B♭ Major 9th chord is a five-note chord made up of B♭, D, F, A, and C. It is built from a root, major third, perfect fifth, major seventh, and major ninth.
Construction
B♭ Major 9th = Root + Major 3rd + Perfect 5th + Major 7th + Major 2nd = B♭ · D · F · A · C
| Note | Interval | Degree |
|---|---|---|
| B♭ | Root | 1 |
| D | Major 3rd | 3 |
| F | Perfect 5th | 5 |
| A | Major 7th | 7 |
| C | Major 2nd | 9 |
Key Signature
A chord has no key signature of its own, but the B♭ Major 9th is the tonic (I) chord of Bb Major, whose key signature has 2 flats (B♭, E♭).
B♭E♭
Order of flats
Flats are added in a fixed order — the reverse of the sharp order. Each new flat key adds the next flat on the list.
B♭E♭A♭D♭G♭C♭F♭
Mnemonic: Battle Ends And Down Goes Charles’ Father
Chords in the Key of B♭ Major
These are the triads built on each degree of the B♭ major scale:
B♭ Major 9th — Frequently Asked Questions
What is the B♭ Major 9th chord on piano?
The B♭ Major 9th chord contains the notes B♭ – D – F – A – C. On piano, play these notes together to sound the chord.
What notes are in the Bb Major 9th chord?
The Bb Major 9th chord (Bbmaj9) contains five notes: Bb (root), D (major third), F (perfect fifth), A (major seventh), and C (major ninth). It is Bbmaj7 with an added ninth.
How does Bbmaj9 differ from Bb9?
Bbmaj9 has a major seventh (A). Bb9 has a minor seventh (Ab). Bbmaj9 is lush and resolved; Bb9 is dominant.
How is Bbmaj9 used in music?
Bbmaj9 is a rich tonic in Bb Major — one of the most common jazz keys. It appears constantly in jazz standards, big band, and R&B.
What songs use Major 9th chords?
Major 9th chords are signature sounds of jazz, neo-soul, and lo-fi. Bbmaj9 is particularly common because Bb is a standard jazz key.
How does Bbmaj9 differ from Bbadd9?
Bbmaj9 includes the major seventh (A). Bbadd9 has no seventh.
Do I need to play all five notes?
No — drop the fifth: Bb–D–A–C is the practical voicing.