Harmonic cadences: how music ends, breathes, and surprises

A cadence is music's punctuation: a short sequence of chords — almost always two or three — that makes a phrase sound finished, suspended, or steered somewhere unexpected. Just as a text uses periods, commas, and ellipses, harmony uses cadences to organize its discourse. In this guide, scale degrees appear as Roman numerals: in C major, I is C, IV is F, and V is G; lowercase letters indicate minor chords, such as vi for Am. Learning to recognize each type by ear changes how you accompany, arrange, and compose, because you start to know where the phrase is headed before it gets there.

The authentic cadence: the period at the end of the sentence

The formula is V7 – I — in C, G7 – C. It is the strongest conclusion the tonal system offers. The dominant chord, in other words the chord built on the fifth degree, carries two unstable notes: the leading tone (in C, the note B, which sits a half step below the tonic and begs to rise to C) and the chord's seventh (the note F, which tends to fall to E). When G7 resolves to C, those two voices settle at the same time, and the ear understands: the phrase is over. The clearer that double resolution, the more conclusive the effect.

The half cadence: the comma that leaves the door open

Here the phrase stops on V — for example, C – Dm7 – G7 — and simply stays there, unresolved. The effect is suspension: any listener can tell the music will continue. In the minor mode there is a famous classic version, the Phrygian cadence: the minor fourth-degree chord in first inversion — that is, with its third in the bass — walks to the dominant, forming iv6 – V (in A minor: Dm/F – E). In practice, the bass descends a half step, from F to E, creating an elegant arrival often used to set up the return of the theme. Note that this classic Phrygian move is a specific half cadence; do not confuse it with the Phrygian modal arrival presented later on.

The plagal cadence: the amen

IV – I, like F – C in the key of C, is the gentle arrival that closes hymns and countless pop choruses. Without the dominant's leading tone, the resolution sounds more restful than dramatic. One expressive variation borrows the minor fourth degree from the parallel minor key: Fm – C. The note Ab in Fm slides down a half step to the G of the arrival chord, and that single moving voice adds an unmistakable melancholy color.

The deceptive cadence: expectation broken

The dominant sets up an arrival on I, but the destination is somewhere else — in its most common form, V – vi, like G7 – Am in C. The ear expected a period and got an ellipsis: the music gains breath for one more lap. Composers use this detour to extend phrases, delay the climax, or spotlight an important word in the lyrics. Strictly speaking, any unexpected destination after the dominant preparation counts as deceptive; vi is simply the most frequent one.

The backdoor: reaching the tonic through the back door

Instead of coming home through the front door (G7 – C), this cadence slips in through the back. The Bb7 is a dominant chord borrowed from the parallel minor key — that is, from C minor, where it lives naturally — and it resolves by rising a whole step to Cmaj7. The notes Ab and F in Bb7 glide smoothly to the G and E of the arrival chord, which explains the soft, nostalgic sound of the move. The backdoor nickname is well established in jazz vocabulary, and the formula appears in standards like Lady Bird, Misty, and Stella by Starlight, as well as plenty of soul, gospel, and Brazilian popular music.

Modal arrivals: conclusion without a dominant

Outside the classic major-minor axis, many styles close phrases without ever calling on V7. Three arrivals are so common they have earned teaching nicknames: bVII – I, associated with the Mixolydian mode (Bb – C when the center is C Mixolydian); IV – i, associated with Dorian (D – Am when the center is A Dorian); and bII – i, associated with Phrygian (Bb – Am when the center is A Phrygian) — in this last one, the major chord built a half step above the tonic is precisely the mode's signature color. A word of caution: these labels are a useful pedagogical convention for organizing the topic, not a single terminology inherited from the classical tradition. What defines a modal arrival is the center established by context — by the melody, the pedal, the repetition — not a fixed formula.

How to study cadences by ear

• Listen to the ending of any song and first sort it into just two boxes: rest (it finished) or suspension (it hung in the air).
• Sing the note that resolves — the leading tone rising or the seventh falling — before you play the arrival chord.
• Play the same cadence in three different keys, saying the degrees out loud: V7 – I, IV – I, V – vi.
• Take a familiar progression and change only the ending: turn an authentic cadence into a plagal one, then a deceptive one, then a backdoor, and compare the effect of each.
• Only speed up once you can predict by ear which cadence is coming next.

Does every song need to end with an authentic cadence?

No. The authentic cadence is the most conclusive, but plagal endings, modal endings, and even a simple fade-out work perfectly well. The choice depends on the style and on how much rest the phrase calls for — a samba, a hymn, and a pop ballad each close in their own way.

What is the difference between the classic Phrygian cadence and the Phrygian modal arrival?

They are different things that share a name. The classic Phrygian cadence is a half cadence in the minor mode (iv6 – V): it ends suspended on the dominant, with the bass descending a half step. The Phrygian modal arrival (bII – i) concludes on the tonic, using the major chord a half step above it as the mode's signature color.

On your instrument

If this scale won you over, the Chord & Fret app plays it along with you — any key, even left-handed. Look it up on the stores.

References

Content reviewed against the standard harmony literature — verified bibliography below.

• Carlos Almada — Harmonia Funcional (Editora da Unicamp, 2009; 2ª ed. 2012)
• Bohumil Med — Teoria da Música (Musimed)
• Stefan Kostka; Dorothy Payne; Byron Almén — Tonal Harmony (McGraw-Hill)
• Edward Aldwell; Carl Schachter; Allen Cadwallader — Harmony and Voice Leading (Cengage)
• Jerry Coker — Elements of the Jazz Language for the Developing Improvisor (Alfred, 1991)
• Open Music Theory

Updated July 9, 2026