Suspended Chords: sus2 and sus4 Construction, Usage, and Resolution

A suspended chord (sus chord) is a triad where the third has been replaced by either the second (sus2) or the fourth (sus4). Because the third is the note that defines major or minor quality, removing it produces a chord that is neither major nor minor — it has an open, ambiguous sound. The replacement note (the 2nd or 4th) is called the suspension. The two most common forms are sus2 (root – second – fifth, e.g. Dsus2 = D–E–A) and sus4 (root – fourth – fifth, e.g. Dsus4 = D–G–A).

Both replace the third of a triad; the difference is which note replaces it. sus2 replaces the third with the major second (2 semitones above the root), giving the formula 0–2–7 and an open, airy, ambient sound. sus4 replaces the third with the perfect fourth (5 semitones above the root), giving the formula 0–5–7 and a tense, expectant sound that wants to resolve back to major. sus2 tends to float without direction; sus4 has a stronger pull toward resolution.

Western harmony conditions the ear to expect a third in every triad — it is what gives a chord its major or minor identity. When you replace the third with a 2nd or 4th, the ear hears the missing third and waits for it to return. The 4th in a sus4 is one semitone above the major third, so it falls down to it easily — this sus4 → major resolution (the V-sus4 → V cadence) is one of the most satisfying moves in popular music. The 2nd in a sus2 rises a whole step to the third, a softer but still directional resolution.

Both are one-finger modifications of the open D major chord (which frets D, G, B, and high-E at the 2nd fret on strings 3, 1, 2 (open) and 2nd fret on string 1). For Dsus4, add your pinky on the high-E string 3rd fret — the G note replaces the F♯ (the major third) and you get D–G–A. For Dsus2, lift the finger that frets the high-E 2nd fret so the string rings open — the E note replaces the F♯ and you get D–E–A. Both shapes resolve back to D by returning the high-E string to its D-major position.