All referees affiliated with FIFA have a designated referee grade. The grade indicates the qualification of the referee to officiate at various levels of local, national and international soccer competition. There is a common misconception that these grades are related to elementary or secondary school grades – they’re not, they are assigned by USSF.
CHANGE for 2019/2020 - Prior referee grades 7, 8 and 9 are now referred to as Grassroots Referees. Prior referee grades 5 and 6 are now referred to as Regional Referees.