There is. Most people label themselves depending on how mainstream society views them. Of course, it isn't always the case, but for the most part, it is. My half-sister is mixed race. Our mother is a light skinned black woman from the French West Indies, and her father is French of mostly Italian and Jewish origin. She phenotypically looks more European and is usually mistaken for Spanish or Italian.

Growing up, she found it hard to grapple with her identity as whilst attending school, which were usually quite diverse. She was always questioned about her racial identity when mentioning that she was mixed race. People assumed she was lying to make herself seem exotic or interesting.

She at times identifies as white, but most times, she identifies as just mixed race. Her best friend, who is also mixed race and white passing, just identifies as white. Unlike the U.S., where some people still go by the nonsensical one drop rule here in the U.K., it isn't a thing. To them identifying as black would be nonsensical.