[1] It is scored for SATB soloists, SATB choir, violin I and II, 2 oboes, 2 clarini (high trumpets), 3 trombones colla parte and basso continuo.

The Credo Mass has been classified as either a missa solemnis,[2] a missa brevis or a missa brevis et solemnis[1] – its performance time of approximately 25 minutes makes it difficult to categorise in a definitive manner.

Its name derives from the long setting of the Credo, in which the word "Credo" is repeatedly sung in a two-note motif.

[3] It thus joins a tradition of so-called "Credo Masses", including Mozart's own Kleine Credo Messe (K. 192) and Beethoven's later Missa solemnis.

This is one of three masses Mozart composed in November and December 1776, all set in C major, including the Piccolominimesse (K. 258) and the Organ Solo Mass (K.