Sharp or Flat?
A Real-World Guide to Chord Spelling That Won’t Get You Laughed Off the Bandstand
In music school, they teach a whole system of rules for how notes are supposed to be spelled.
When to call something C♯. When to call it D♭. When to call it B##.
I’ve never completely understood it.
But I can tell you this: in the real world, it’s pretty useless.
This is not a guide for the classroom.
This is how it works in the real world—specifically in the worlds of chord charts, lead sheets, Ultimate Guitar, The Real Book—and especially at a jam session when guys are yelling out chord names.
Try this experiment:
Call out A♯ instead of B♭ at a jazz jam.
Watch the facial expressions.
It’s a rookie move. Everyone hears it. No one forgives it.
Start With the Easy Ones
There are seven notes that never change:
A
B
C
D
E
F
G
No one debates how to spell these.
You’ll see them in every genre, every chart, every context—unchanged.
The Real Question: What About the Other Five?
There are five notes that sit between the naturals.
Each one can be spelled two ways:
These five are where all the real-world decisions happen.
This guide is about those decisions.
Rule #1: Don’t Mix Systems
Never combine sharps and flats in the same chart.
Choose either all sharps or all flats—and stick with it for the whole song.
C♯m and D♭ in the same progression?
That’s just not done.
It looks ugly on paper and sounds ugly when spoken.
Rule #2: B♭ and E♭ Are Always Flat
These two are special cases.
You’ll find them in every genre—rock, pop, jazz, funk, metal, anything.
Why? I have no idea.
But I can tell you that I practically never see A♯ and D♯ chords.
So the rule is simple:
Always write B♭ instead of A♯.
Always write E♭ instead of D♯.
Rule #3: Let Genre Decide the Rest
That leaves three enharmonic tones where either spelling could work:
C♯ / D♭
F♯ / G♭
G♯ / A♭
Here’s how to choose:
If the song is rock, pop, or guitar-driven:
Use sharps:
C♯m
F♯
G♯7
If the song is jazz, soul, R&B, or piano-driven:
Use flats:
D♭maj7
G♭m7
A♭7
This matches Real Book convention and horn-friendly keys.
Pianists are also used to flat-heavy notation in common jazz keys.
What If the Rules Clash?
Let’s say you’ve got a rock song in C major, but it uses a B♭ chord.
Now you’ve got a problem.
The genre calls for sharps.
The chord demands a flat.
Here’s what to do: break the genre rule.
You don’t respell B♭ as A♯ just to keep everything sharp.
That looks ridiculous, and nobody wants to read it.
So you let the B♭ in.
And once you’ve done that, you switch the whole chart to flats—E♭ instead of D♯, A♭ instead of G♯, etc.—even if it’s a little out of place for a rock song.
The B♭ overrules everything.
Because A♯ isn’t welcome, no matter what the style is.
Rule #4: No Double Sharps
F## is not a chord.
C##7 doesn’t exist on a lead sheet.
If you see a double sharp in a chord name, it means:
A robot made the chart.
Someone got lost in theory class and didn’t come back.
I’m not going to try to come up with some convoluted explanation of why these unspoken rules exist.
It’s just the way it is.
I don’t try to fight them.
I just join them.