How far do pre-employment criminal background checks go back? Some websites claim 7 or 10 years, while other sites claim that criminal background checks can go back to age 18. How far back in an applicant's history does an employer go to determine which records to check? The most common employment background check requested by our clients is: A current Social Security Number Scan. County Criminal Record Checks for counties in which an applicant lived, worked, and went to school during the last seven years. Employment Verifications for employers for which the applicant worked during the past seven years.