A nonchord tone (NCT) is a pitch that doesn't belong to the chord sounding underneath it, used to embellish a melody or smooth voice leading. On the AP Music Theory exam you classify NCTs by how they're approached and left, such as passing tones, neighbor tones, suspensions, and anticipations.
A nonchord tone (also called a nonharmonic tone or embellishing tone) is any pitch that isn't a member of the chord currently sounding. If the harmony is a C major triad (C-E-G) and the melody touches a D, that D is a nonchord tone. It creates a brief dissonance against the chord, and in Common Practice Era style that dissonance has rules about how it arrives and how it resolves.
The whole game is classification by approach and departure. A passing tone fills the gap between two chord tones by step (approached by step, left by step in the same direction). A neighbor tone steps away from a chord tone and steps right back. A suspension holds a note over from the previous chord, creating dissonance on the strong beat, then resolves down by step. An anticipation arrives at the next chord's pitch early. An appoggiatura leaps in and resolves by step. AP Music Theory expects you to name these by their motion pattern, not just flag a note as "wrong." In fact, NCTs are never wrong by default. They're stylistically correct when they follow these conventions and incorrect when they don't (like a suspension that resolves up, which is actually a retardation, or a dissonance that just gets abandoned).
Nonchord tones sit at the intersection of melody and harmony, which is exactly where AP Music Theory lives. You can't do accurate Roman numeral analysis without filtering out NCTs first. If you treat a passing tone as a chord member, you'll misidentify the chord, get the inversion wrong, and lose points on analysis questions. The same skill drives harmonic dictation. When you hear a melody over a progression, your brain has to sort which pitches define the harmony and which ones are decoration.
NCTs also matter in the part-writing direction. The four-part voice-leading FRQs follow eighteenth-century procedures, where dissonance treatment is strict. Knowing that a suspension must be prepared, sounded, and resolved down by step is the difference between a clean realization and a voice-leading error. This concept threads through every harmony unit on the exam, from basic triads through chromatic harmony, because composers in every period decorate chords the same handful of ways.
Keep studying AP® Music Theory Unit 6
Visual cheatsheet
view galleryChordal Seventh (Units 3-4)
The chordal seventh is the trap that looks like an NCT but isn't. In a V7 chord, the seventh is dissonant and resolves down by step just like a suspension, but it's a real chord member. The resolution behavior is identical; the analysis is different. Ask yourself whether the dissonant note fits the chord symbol before you label it an NCT.
Tendency Tones (Units 2-4)
Tendency tones (like the leading tone and chordal seventh) and NCTs share the same logic, which is that dissonance and instability demand stepwise resolution. If you understand why the leading tone pulls up to tonic, you already understand why a suspension pulls down to its resolution. It's the same gravitational rule applied to different notes.
Harmonic Rhythm (Unit 4)
You can't identify NCTs until you know where one chord ends and the next begins. Harmonic rhythm tells you which notes sound "during" a given chord, and from there you sort chord tones from embellishments. Fast harmonic rhythm means fewer NCTs per chord; slow harmonic rhythm leaves room for lots of decoration.
Common Practice Era (all units)
The NCT rules you memorize aren't universal laws of music. They're conventions of roughly 1650-1900 European music, which is the style the AP exam tests. That's why the part-writing FRQs say "following eighteenth-century voice-leading procedures." Outside that style, composers break these rules constantly.
Nonchord tones show up in three main places. First, multiple-choice score analysis, where a circled note in an excerpt comes with the question "this pitch is best described as a..." and you pick from passing tone, neighbor tone, suspension, appoggiatura, and so on. The answer always comes down to approach and departure, so check the note before and the note after. Second, Roman numeral analysis, where you have to mentally strip out the NCTs to find the actual chord. Third, the part-writing FRQs. The 2025 exam's Question 7 asked for a bass line and Roman numerals "following eighteenth-century voice-leading procedures," and that phrase is your cue that dissonances must be handled by the rules: suspensions prepared and resolved down by step, passing tones filling stepwise gaps, no abandoned dissonances. Harmonic dictation also rewards this skill, since hearing which melody notes are decorative keeps you from writing the wrong chord.
Both are dissonant and both resolve down by step, so they sound and behave almost identically. The difference is membership. The seventh of a V7 chord is part of the chord, so it appears in the Roman numeral analysis (that's the 7 in V7). A nonchord tone is outside the chord entirely and never appears in the chord symbol. Quick test: spell the chord from the Roman numeral. If the dissonant note is in the spelling, it's the chordal seventh; if not, it's an NCT.
A nonchord tone is any pitch that doesn't belong to the chord sounding beneath it, and you classify it by how it's approached and how it's left.
Passing tones move by step in one direction between chord tones, while neighbor tones step away from a chord tone and step back to it.
A suspension is prepared as a chord tone, held over into the new chord to create dissonance on the strong beat, and resolved down by step.
Before doing Roman numeral analysis, filter out the NCTs, because treating a decorative note as a chord member leads to the wrong chord or inversion.
The chordal seventh resolves down by step just like a suspension, but it's an actual chord member, not a nonchord tone.
On part-writing FRQs, "eighteenth-century voice-leading procedures" means every dissonance needs a proper approach and a stepwise resolution.
A nonchord tone is a pitch that doesn't belong to the chord currently sounding, used to embellish the melody or smooth voice leading. The exam expects you to identify specific types like passing tones, neighbor tones, suspensions, anticipations, and appoggiaturas based on how each is approached and resolved.
No. Nonchord tones are a normal, expected part of Common Practice Era music, and composers use them constantly. They're only "incorrect" when they break style conventions, like a dissonance that doesn't resolve by step or a suspension resolved in the wrong direction.
A chordal seventh (like the F in a G7 chord) is a real member of the chord and shows up in the Roman numeral, while a nonchord tone is outside the chord entirely. Both resolve down by step, so spell the chord from its symbol to check whether the dissonant note belongs.
A passing tone moves by step in one continuous direction, connecting two different chord tones (like C-D-E). A neighbor tone steps away from a chord tone and returns to the same note (like C-D-C). Direction of motion is the whole distinction.
First find the chord using the bass note and the pitches that align with the harmonic rhythm, then label any leftover pitches as NCTs based on their approach and departure. Step-step in one direction is a passing tone, step-and-return is a neighbor, and a held-over note resolving down by step is a suspension.
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