|Relative key||C minor|
|Parallel key||E-flat minor|
|Dominant key||B-flat major|
|E♭, F, G, A♭, B♭, C, D|
E-flat major (or the key of E-flat) is a major scale based on E♭, consisting of the pitches E♭, F, G, A♭, B♭, C, and D. Its key signature has three flats. Its relative minor is C minor, and its parallel minor is E♭ minor, (or enharmonically D♯ minor).
The E-flat major scale is:
The key of E-flat major is often associated with bold, heroic music, in part because of Beethoven's usage. His Eroica Symphony, Emperor Concerto and Grand Sonata are all in this key. Beethoven's (hypothetical) 10th symphony is also in the key of E-flat major. But even before Beethoven, Francesco Galeazzi identified E-flat major as "a heroic key, extremely majestic, grave and serious: in all these features it is superior to that of C."
Three of Mozart's completed horn concertos and Joseph Haydn's Trumpet Concerto are in E-flat major and so is Anton Bruckner's Fourth Symphony with its prominent horn theme in the first movement. Another notable heroic piece in the key of E-flat major is Richard Strauss's A Hero's Life. The heroic theme from the Jupiter movement of Holst's The Planets is in E-flat major. Mahler's vast and heroic Eighth Symphony is in E-flat and his Second Symphony also ends in the key.
However, in the Classical period, E-flat major was not limited to solely bombastic brass music. "E-flat was the key Haydn chose most often for [string] quartets, ten times in all, and in every other case he wrote the slow movement in the dominant, B-flat." Or "when composing church music and operatic music in E-flat major, [Joseph] Haydn often substituted cors anglais for oboes in this period", and also in the Symphony No. 22 in E-flat major.
For Mozart, E-flat major was associated with Freemasonry; "E-flat evoked stateliness and an almost religious character."
Elgar wrote his Variation IX "Nimrod" from the Enigma Variations in E-flat major. Its strong, yet vulnerable character has led the piece to become a staple at funerals, especially in Great Britain.