I–III–IV–iv in A Major

Pattern: I – III – IV – iv Chords: A – C♯ – D – Dm

Chord Breakdown

Numeral	Chord	Type	Function
I	A (details)	major	Tonic
III	C♯ (details)	major	Mediant
IV	D (details)	major	Subdominant
iv	Dm (details)	minor	Subdominant

Harmonic Analysis

This progression moves through A (Tonic) → C♯ (Mediant) → D (Subdominant) → Dm (Subdominant).

The I–III–IV–iv progression features a chromatic ascent from I to IV via a secondary dominant III, then darkens with a borrowed minor iv. The III chord (V/vi) adds unexpected brightness while the iv creates a ♭ittersweet descent. This pattern appears in classic rock and singer-songwriter music.

Song Examples

Something — The Beatles
My Girl — The Temptations

Chord Details

A C♯ D Dm

More Progressions in A Major

I–IV–V–I I–V–vi–IV I–vi–IV–V ii–V–I I–IV–V I–♭VII–IV vi–IV–I–V I–V–vi–iii–IV–I–IV–V I–IV I–V IV–V IV–I