Sound! Euphonium: Welcome to the Rikka High School Marching Band

'Sound! Euphonium: Welcome to Rikka High School Marching Band' is a spin-off novel of the Sound! Euphonium series published in two volumes. The first volume was published on August 4, 2016, while the second volume was published on September 6, 2016 by Takarajimasha.

Synopsis
The story focuses on Rikka High School Marching Band. Azusa Sasaki, Kumiko's friend from the middle school, is the main character of this novel. The story is set in about the same time as the main series but it is told from Rikka High School's perspective instead of Kitauji's.