The standard grips this chord is usually shown with.
Bbm11 is Bb, Db, F, Ab, C and Eb, a minor eleventh. The shape this page opens on is written 646544, lowest string first.
Note by note. Bb is the root, Db is the minor third, F is the fifth, Ab is the flat seventh, C is the ninth and Eb is the eleventh.

Also written Bbmin11, Bb-11 or Bb minor 11. The same chord either way; which spelling you meet depends on who wrote the chart.
There are 7 common shapes for Bbm11 on the guitar, and 52 derived voicings in 4 families.
One note away. Change a single note of Bbm11 and you have Bbm9 (with one note taken away), BbmMaj11 (with one note moved) or Bb11 (with one note taken away).
In which keys. Every note of Bbm11 belongs to C# major (the vi), F minor (the iv), Ab major (the ii) and Bb minor (the i).
The common shapes, written lowest string first: 646544, 6x664x, 666668, xx8899, x-13-11-13-11-11, x-13-11-13-13-11, x-13-13-13-14-13.
Under the hand. None of the shapes for Bbm11 uses an open string, so every one of them is movable; the lowest sits at the 4th fret. 6 of the 7 need a barre. Together they cover the neck from the 4th fret to the 14th.
Shell. Root, third and seventh: the guide tones fix the quality, so the fifth is dropped. That is what leaves a string free, so pick a tension to put on top. Bbm11 has 6x664x, 6468xx, x-13-x-13-14-11, x1664x, 6-11-11-8-x-x, x-x-8-6-9-11.
Drop 2. A close-position chord with the second voice from the top lowered an octave. Sits on four adjacent strings. Bbm11 has x1112x, xx6646, 6666xx, xx8899, 11-13-11-13-x-x, x-x-11-13-11-11, x-13-13-13-14-x, xx1324.
Drop 3. The third voice from the top lowered an octave. The dropped voice becomes the bass, which is why a string is skipped. Bbm11 has 4x132x, x4x344, 6x664x, x6x696, 9x889x, x-11-x-8-11-9, 11-x-11-13-11-x, x-13-x-13-14-11.
Rootless. The root left to the bass player. Frees a finger for a tension. Bbm11 has x3112x, xx1121, x4654x, x6666x, x-x-10-8-9-9, x-x-11-10-9-11, x-x-11-13-13-11, x-15-13-13-14-x.
Tensions. A shell of Bbm11, root, third and seventh, leaves a string free, and the tones that belong over it are the 13 (G).
What kind of chord this is. Bbm11 is a minor chord — root, minor third, fifth. minor chords on every root, and what they are for.
The common 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.