What is a Secondary Leading-Tone Chord?

A secondary leading-tone chord is a chord built on the leading tone of a chord other than the tonic, temporarily emphasizing that chord as if it were a tonic. In other words, it functions like a leading-tone chord that resolves to a specific chord within the key rather than to the main tonic.

In tonal harmony, the leading tone is the note that sits a half step below a target note and strongly resolves upward to it. A secondary leading-tone chord uses this principle to briefly highlight another chord in the progression. For example, in the key of C major, a leading-tone chord built on F♯ (the leading tone of G) would resolve to a G major chord, which is the dominant in the key of C.

These chords are often labeled using Roman numerals such as vii°/V, which means “the leading-tone chord of the dominant.” Secondary leading-tone chords add harmonic interest and strengthen the pull toward specific chords within a progression, making the harmony sound more dynamic and directional.