I–III–IV–iv in F Major

Pattern: I – III – IV – iv Chords: F – A – B♭ – Bbm

Chord Breakdown

Numeral	Chord	Type	Function
I	F (details)	major	Tonic
III	A (details)	major	Mediant
IV	B♭ (details)	major	Subdominant
iv	Bbm (details)	minor	Subdominant

Harmonic Analysis

This progression moves through F (Tonic) → A (Mediant) → B♭ (Subdominant) → Bbm (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

F A B♭ Bbm

More Progressions in F 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