The standard grips this chord is usually shown with.
BbmMaj7 is Bb, Db, F and A — Bbm with the major seventh added on top.
It sounds tense and wrong-footed. A minor triad carrying a major seventh: the semitone under the root over a minor chord is the first bar of a line cliché.

| Bb | Db | F | A |
|---|---|---|---|
| 1 | ♭3 | 5 | 7 |
Minor tonic — the tonic of the melodic minor.
Also written BbmM7, Bbm(maj7), Bb-Δ7 or BbminMaj7. The same chord either way; which spelling you meet depends on who wrote the chart.
BbmMaj7 in 1st inversion puts Db in the bass instead of Bb, the 3rd of the chord. The notes are the same; what changes is what the bass line does, which is most of why you would reach for it — it lets the lowest voice move by step where the root would have jumped.
One of BbmMaj7’s 7 common shapes does this: x43365.
Start with xx8665 — no barre and low, at the 5th fret. None of the shapes for BbmMaj7 uses an open string, so every one of them is movable; the lowest sits at the 1st fret. 1 of the 7 needs a barre. Together they cover the neck from the 1st fret to the 15th.
| Frets | Where | Bass | Top | Hand |
|---|---|---|---|---|
| x13221 | 1st fret | Bb, root position | F | all fretted |
| x43365 | 3rd fret | Db, 1st inversion | A | all fretted |
| xx8665 | 5th fret | Bb, root position | A | all fretted |
| 687666 | 6th fret | Bb, root position | Bb | barred |
| x-x-8-10-10-9 | 8th fret | Bb, root position | Db | all fretted |
| x-13-11-10-10-x | 10th fret | Bb, root position | A | all fretted |
| x-13-15-14-14-13 | 13th fret | Bb, root position | F | all fretted |
The same notes rebuilt from scratch give 5 shell, 13 drop 2, 9 drop 3 and 2 open string voicings, each on its own page.
Tensions. A shell of BbmMaj7, root, third and seventh, leaves a string free, and the tones that belong over it are the 9 (C), the 11 (Eb) and the 13 (G).
How you get to it. The turn that lands on BbmMaj7 is Cm7♭5 to F7♭9: the ii and the V of Bb minor, which is where a minor tonic is usually arrived at rather than simply begun on.
Every note of BbmMaj7 is in Bb harmonic minor and Bb melodic minor.
Change one note of BbmMaj7 and you have Bbm (drop the major seventh), Bbmaj7 (the minor third becomes a major third), Bbm6 (the major seventh becomes a sixth), Bbm7 (the major seventh becomes a flat seventh), BbmMaj7b5 (the fifth becomes a flat fifth) or BbmMaj9 (add the ninth).
BbmMaj7 is a minor chord — root, minor third, fifth. Minor chords on every root.
On BbmMaj7’s sound and use this page follows Mark Levine, The Jazz Theory Book (Sher Music, 1995). The shapes and the derived voicings come from different places, and both are explained in where the chords and the theory come from.
Shows each chord the way this style would voice it, and marks which of its alternatives belong to the idiom.