CMC15 is an astrometric and photometric catalogue of more than 122.7 million stars in the magnitude range 9 < r' (SDSS) < 17. With a positional accuracy to about 35 mas, the catalogue covers the declination range -40deg to 50deg. The current release comprises all the observations made between March 1999 and March 2011. The catalogue fills the gap between 5h 30m and 10h 30m for declinations south of -15deg of the CMC14 and adds the bans -30deg to -40deg. Some zones north of -30deg have also been re-observed in order to improve their internal errors.