Flat key signatures cover seven of the twelve major keys: F, B♭, E♭, A♭, D♭, G♭, and C♭ major. Each one adds one more flat to the staff in a fixed order, and learning that order is the fastest way to recognize any flat key signature at a glance.

This is part 3 of our key signatures series. Part 1 covers the basics and the full chart, and part 2 covers sharp major keys. This guide lists every flat major key signature, shows it on the staff, gives the relative minor that shares each signature, and explains the trick to identify any flat key from its signature.

Major key signatures with flats

The seven major keys that use flats are F, B♭, E♭, A♭, D♭, G♭, and C♭ major. Each adds one flat to the previous key, following a fixed sequence: B♭, E♭, A♭, D♭, G♭, C♭, F♭. The order is the exact reverse of the order of sharps.

F major key signature (1 flat)

F major has one flat: B♭. The key signature appears at the start of each line of music, telling you to play B as B♭ throughout the piece. It shares this one-flat signature with its relative minor, D minor.

F major key signature on the staff

In the score below, the first two bars show the F major scale written with no key signature (every B is explicitly flat). The next two bars use the proper F major key signature; once you set it, you don't need to write the ♭ on every B.

B♭ major key signature (2 flats)

B♭ major has two flats: B♭ and E♭. It's one of the most common keys in concert band and jazz repertoire because many wind instruments are pitched in B♭. Its relative minor is G minor.

B flat major key signature on the staff

E♭ major key signature (3 flats)

E♭ major has three flats: B♭, E♭, and A♭. Another favorite for brass and big band writing. Its relative minor is C minor.

E flat major key signature on the staff

A♭ major key signature (4 flats)

A♭ major has four flats: B♭, E♭, A♭, and D♭. Common in romantic piano repertoire (Chopin used it extensively). Its relative minor is F minor.

A flat major key signature on the staff

D♭ major key signature (5 flats)

D♭ major has five flats: B♭, E♭, A♭, D♭, and G♭. Its relative minor is B♭ minor.

D flat major key signature on the staff

G♭ major key signature (6 flats)

G♭ major has six flats: B♭, E♭, A♭, D♭, G♭, and C♭. It's the enharmonic equivalent of F♯ major (6 sharps); they sound identical but are written differently. Its relative minor is E♭ minor.

G flat major key signature on the staff

C♭ major key signature (7 flats)

C♭ major has all seven flats: B♭, E♭, A♭, D♭, G♭, C♭, and F♭. F♭ is the same pitch as E natural, but in this key it's written as F♭ to keep one note of each letter name. C♭ major is rare and is usually written enharmonically as B major (5 sharps) for easier reading. Its relative minor is A♭ minor.

C flat major key signature on the staff

How to memorize flat key signatures

The flats always appear in the same order on the staff, no matter the key: B♭, E♭, A♭, D♭, G♭, C♭, F♭. A common mnemonic is "Battle Ends And Down Goes Charles' Father," the exact reverse of the order of sharps.

Finding the key from the signature

For flat key signatures, the trick is different from sharps. If there's only one flat (B♭), the key is F major. There's no shortcut for this one, so just memorize it.

For two or more flats, look at the second-to-last flat. That tells you the key. If the last two flats are B♭ and E♭, the second-to-last is B♭, and the key is B♭ major. If the flats are B♭, E♭, A♭, D♭, G♭ (5 flats), the second-to-last is D♭, and the key is D♭ major.

Finding the signature from the key

If you know the key and need to write the signature, count up from F: F (1 flat), B♭ (2), E♭ (3), A♭ (4), D♭ (5), G♭ (6), C♭ (7). Or memorize the major scales: once you know A♭ major is spelled A♭, B♭, C, D♭, E♭, F, G, A♭, you can count the flats directly (4 in this case).

Once you can read the signatures, choosing between them is the next step. Our guide to music keys and their emotions maps how each key tends to feel.

Practice flat key signatures in Flat

The fastest way to internalize these is to write scales in them. Open a new score in Flat, set each flat key from the toolbar, write its major scale, and play it back to connect the look of the signature with its sound. Start with F major (one flat) and add a flat each time until you reach C♭ major.

💡 How to add or change a key signature in Flat.

Key signatures series

FAQ

How many major keys use flats?

Seven: F, B♭, E♭, A♭, D♭, G♭, and C♭ major. Each adds one more flat than the last, following the order B♭, E♭, A♭, D♭, G♭, C♭, F♭.

How do you identify a major key from a flat key signature?

For two or more flats, look at the second-to-last flat: that note names the key. The one exception is a single flat (B♭), which is always F major and has to be memorized.

What is the order of flats in a key signature?

B♭, E♭, A♭, D♭, G♭, C♭, F♭, the exact reverse of the order of sharps. A common mnemonic is "Battle Ends And Down Goes Charles' Father."

Which major key has the most flats?

C♭ major, with all seven flats. It is rare and is usually written enharmonically as B major, which uses five sharps and is easier to read.

What are the relative minors of the flat major keys?

Each flat major key shares its signature with a minor key: D minor (F major), G minor (B♭ major), C minor (E♭ major), F minor (A♭ major), B♭ minor (D♭ major), E♭ minor (G♭ major), and A♭ minor (C♭ major).