The British Cycling Cyclocross age categories for the 2025/26 season are as follows (effective from 1st Sept 2025):

Under 8 born in 2018 or later
Under 10 born in 2016 or 2017
Under 12 born in 2014 or 2015

Youth – born 2010 to 2013
Youth – Under 16 – born 2010 or 2011
Youth – Under 14 born 2012 or 2013

Junior – born 2008 or 2009

Under 23 – born 2004 to 2007

Senior born – 2003 or earlier

Masters 40+ born between 1976 and 1985
Masters 40 born 1981 to 1985
Masters 45 born 1976 to 1980

Masters 50+ born 1975-1966
Masters 50 born 1971 to 1975
Masters 55 born 1966 to 1970

Masters 60 born 1965 or before
Masters 65 born 1956 to 1960

Masters 70+ born 1955 or earlier