Cadences — how phrases end
Cadences are the punctuation marks of music. Authentic, plagal, deceptive, and half cadences each create a different kind of 'pause' at the end of a phrase.
What a cadence is (and why your ear notices)
A cadence is a two-chord (sometimes three-chord) pattern at the end of a musical phrase that creates a sense of arrival, suspension, or surprise. Just as written language uses commas, semicolons, periods, and question marks, harmony uses cadences to signal 'pause', 'continue', 'done', or 'unresolved'.
All four classical cadences are built from the diatonic chords of a single key. The differences come from which chord you land on, not what you build the chord out of.
Authentic cadence — V → I
The strongest, most final resolution in tonal music. V contains the leading tone (the 7th degree of the scale), which pulls up a half-step into the tonic. Every classical symphony ends with one. In C major: G → C. In G major: D → G.
Make it stronger by using V7 (G7 → C) — the added flat-7 forms a tritone with the 3rd of V, doubling the pull toward I. This is the cadence that signals 'the song is over'.
Perfect authentic cadence in C: G7 → C. The most final sound in Western music.
Plagal cadence — IV → I
Softer, more peaceful than authentic. No leading tone, so the resolution feels relaxed rather than inevitable. Sometimes called the 'amen cadence' because it's how hymns end the final 'amen'. In C: F → C. Very common in folk, ballads, and gospel.
Plagal cadence in C: F → C. The 'amen'.
Deceptive cadence — V → vi
You set up V → I and then refuse to deliver it. Instead of resolving to the tonic, V slides to vi (the relative minor) — which shares two of the three tonic notes but feels bittersweet, suspended, unfinished. In C: G → Am.
Songs use the deception to extend a phrase ('one more time…') or to colour an emotional moment. The Beatles loved it.
Deceptive cadence in C: G → Am. You expected C — you got Am.
Half cadence — anything → V
End the phrase on the V chord and stop. Because V demands resolution but you're not giving it, the phrase sounds like a question. Composers use half cadences before a chorus to set up the resolution that's about to come.
Common approach: ii → V (Dm → G in C) or IV → V (F → G in C). The progression ends on V with the listener expecting the next phrase to resolve to I.
Approach to a half cadence in C: ii → V. Sounds like 'and then…?'
ii–V–I — the pre-cadence
Jazz and standards added one more chord in front of the authentic cadence: the ii chord. In C: Dm → G → C. The ii sets up the V more strongly than the I → V approach (ii contains the same notes as IV plus the 2nd, leading you smoothly into V). Add 7ths and you get the classic Dm7 → G7 → Cmaj7 — the most-played progression in jazz.
ii–V–I in C major. Practice this in every key and you'll have the keys of jazz.
Spotting cadences by ear
- If the phrase ends and feels finished, it's almost certainly authentic (V→I) or plagal (IV→I). The difference: authentic has a strong leading-tone pull; plagal is gentle.
- If the phrase ends and feels suspended like a question, it's a half cadence on V.
- If the phrase resolves to a minor chord when you expected a major one, it's a deceptive cadence to vi.
Try this: play C–F–C–G–C (I IV I V I) and then C–F–C–G–Am. The first ends; the second hangs. That's the entire difference between authentic and deceptive in one experiment.
Practice this week
- Play each cadence in C, then G, then D. Same chord roles, different shapes.
- Listen to the last 10 seconds of three of your favourite songs. Identify which cadence each one ends on.
- Write a 4-bar phrase that ends on a half cadence. Then a 4-bar phrase that answers it with an authentic cadence. You've just written a question-and-answer period — the basic building block of every song form.