What major factor determines the level of a security clearance?

The level of a security clearance is primarily determined by the results of an individual's background investigation. This investigation assesses various aspects of the individual’s personal history, including criminal records, financial responsibility, and overall reliability and trustworthiness. The objective is to ensure that the person can be trusted with access to sensitive or classified information. The thoroughness and findings of the background investigation directly influence the adjudication process, which determines whether an individual is eligible for, and at what level, security clearance.

Factors such as financial stability of the organization, employee tenure, or the number of employees within a facility do not directly affect an individual's security clearance. While these aspects might play a role in broader organizational security protocols or operational effectiveness, the specific determination of security clearance is individual-focused and relies heavily on the integrity and reliability of the background check outcomes.