Borrowed Chords: A Five-Minute Primer

Bakers have a trick that sounds wrong the first time you hear it: a pinch of salt in a sweet recipe. Not enough to taste as salt.. just enough to make the sugar taller. Borrowed chords are the songwriting equivalent. You reach out of the key your song lives in, take a single chord that technically belongs somewhere else, and drop it in. Used sparingly, nobody hears "wrong." They just hear that the song suddenly has more depth than its handful of chords should be able to afford.

What "borrowed" actually means

Every major key has a parallel minor. The same home note, a different set of notes stacked above it. C major and C minor are parallels: both call C home, but C minor flattens the third, sixth and seventh degrees of the scale. Borrowing — its proper name is modal interchange — is simply this: while you are in C major, you are allowed to step next door into C minor, pick one chord up off the shelf, and carry it back. Because the home note never changes, the song does not feel like it has changed key. It has only, for a moment, changed weather.

I solved a times newspaper cryptic crossword this morning (and part of the afternoon) and a borrowed chord works on the ear the way a good cryptic clue works on the eye. For a beat it looks like a mistake. Then it resolves, and you realise it was fair all along. You were led somewhere you did not expect, and the surprise was the whole point.

The four worth knowing first

There are more borrowed chords than these, but four of them do most of the work in popular songwriting. I will write them in Roman numerals and give each example in C major, so you can move them into any key you like.

The minor iv iv

If you only ever borrow one chord, borrow this one. In C major the IV chord is F major; its borrowed cousin is F minor. Slip the minor iv in where the major IV would normally sit, most powerfully on the way home to the I and you have the single most recognisable bittersweet move in popular music. It works because of one flattened note, the A♭ hiding inside that F minor, which leans downward into the tonic with a soft, reluctant pull. Play C – F – Fm – C and listen to the third chord. That is the sound of a happy memory you are standing just outside of.

The flat seven ♭VII

Borrowed from the minor key's flattened seventh degree, ♭VII in C major is a B♭ major chord. It sits a whole step below home, which lets it shove the song back up to C with real momentum. C – B♭ – F – C has powered anthemic choruses for sixty years. It sounds open and faintly defiant. It steps around the polite, classical leading-tone resolution and simply leans in.

The flat six ♭VI

♭VI in C major is A♭ major, built almost entirely from notes the key does not own. It has a way of making a song feel as though it has walked outside and looked up. String it together as ♭VI – ♭VII – I — that is A♭ – B♭ – C. And you have a triumphant little staircase you will recognise the instant your hands find it. Save it for the moment a chorus needs to feel bigger than the verse has any right to make it.

The Picardy third

The other three borrow from minor into major. This one borrows the other way. If your song lives in a minor key, the final chord ought to be minor too - but raise its third at the very last moment and you get the Picardy third: a centuries-old move that ends a sad song on a sudden, narrow shaft of light. It is the most loaded single-note change available to you. Spend it once, at the very end, and never explain it.

One borrowed chord is a flavour. Three is a different song that has lost track of its key.

How to borrow without overspending

Every writer makes the same mistake the week they discover modal interchange, and it is exactly the mistake a new baker makes with salt: more. A borrowed chord's power is entirely relative - it lands because everything around it is diatonic and behaving itself. Keep the rest of the progression honest, and let the one outsider do its work. If a section has two borrowed chords fighting for attention, the surprise cancels out and you are left with something merely murky.

The fastest way to feel any of this is to hear it back to back. Open the free chord progression builder at Undercover Zest, lay down a plain, well-behaved progression, then swap a single chord for its borrowed version and play both. The builder has a modal-interchange mode for exactly this - it shows you which borrowed chords are genuinely available in your key, so you are choosing rather than guessing. If you want somewhere to practise, the progressions in 10 versatile chord progressions every songwriter should know all take a borrowed chord beautifully.