Sus 4 Chords Explained
‘Sus 4’ is short for ‘suspended 4th’.
In classical music, the ‘sus 4 chord’ plays a 4th instead of the 3rd (1 4 5). The 4th adds a tension, which then resolves to the 3rd a few beats later.
Suspended 4ths are normally applied to major triads, or V7 chords:

However in jazz, sus 4 chords do not resolve to the 3rd. Instead they hold the tension throughout the chord:

Here are two of my favorite chord voicings for a ‘C7 sus 4’ chord:
First, you can simply play a Bb major triad over C - this chord voicing can be heard famously in 'Song For My Father' by Horace Silver:

Or you can play a Bb major 7 chord in your right hand, over C in the bass:

Sometimes I'll double my left hand in octaves (C - C) to add more bass to these chord voicings.
FREE RESOURCE: For more jazz piano chord voicings, you can download my free ‘Jazz Piano Chord Voicing Guide' which shows you 5 types of chord voicing used by professionals (shells, 4th voicings, rootless voicings, and more). Click here to download
Slash Chord Notation
Most of the time, sus 4 chords will be written ‘C7sus4’. However, some arrangers will use ‘slash chord’ notation instead...
'Slash chords' are a notation style you'll sometimes encounter in jazz. They consist of two letters with a slash in-between. The first letter (before the slash) tells you a chord to play in your right hand (e.g. 'Bb maj 7'), and the second letter (after the slash) tells you which bass note to play in your left hand (e.g. 'C').
Common slash chords you might see for C7sus4 include ‘Bb/C’, ‘Gm7/C’, or ‘Bb maj 7/C’. Each of these slash chords creates the sound of C7sus4.
Left-Hand Sus Voicings
You can also voice a sus 4 chord in your left hand by playing a stack of 4ths - like this:

The first voicing seen above can be used for a C7 sus 4 chord, or a C minor 7 chord with a sus 4 sound.
This is also a nice voicing to use when accompanying yourself soloing in your right hand. If you have 8 bars of a ‘C min 7’ chord, you could alternate between C7 sus 4 and D7 sus 4 - using the 4th voicing shown above.
When To Play Sus 4 Chords
Sus 4 chords are quite rare in lead sheets. You’ll encounter them in a few songs, such as ‘Song For My Father’ by Horace Silver (my favorite use of this chord).
But there’s nothing to stop you from ‘reharmonizing’ a song’s chords and playing V7 chords with a sus 4 instead.
All Jazz Chords – Review
Here's my 3-minute run through of all common Jazz chords – from 7ths, 9ths, 11ths, 13ths, altered, and more:
Next step
If you’d like the full written version of my Ultimate Jazz Piano Guide — an encyclopedia-style lesson covering Jazz piano theory, chords, voicings, scales, improvisation and harmony — explore it here:
Or focus on one area:
Jazz Piano Fundamentals →
Chord Voicings →
Improvisation →

I’m Julian Bradley, founder of Jazz Tutorial.
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