maybe you can check out a thread asking the similar question on businessweek forum. a bachelor's degree is required for most MBA programs in the states, while some programs in UK may lessen this requirement if the applicant is strong in other sense. actually if you look up at MBA brochure of most schools, you may note that they seldom set the strict line in terms of GPA, GMAT (though we all know they do have bottom line to screen applications, they just avoid stating that to shed potential applicants), but a bachelor's degree is explicitedly stated as prerequisite for application.