Tier 3 / Tier 5 Investigations
Tier 3 and Tier 5 are standardized levels of background investigation used for security clearances. The tier system replaced older investigation names (NACLC, SSBI) to create a unified federal framework.
Quick Facts
| Tier 3 | For Secret and Confidential clearances |
| Tier 5 | For Top Secret and SCI eligibility |
| Authority | Federal Investigative Standards |
| Conducted by | DCSA (for most positions) |
Investigation Tier Comparison
| Aspect | Tier 3 | Tier 5 |
|---|---|---|
| Clearance level | Secret / Confidential | Top Secret / SCI |
| Subject interview | Only if issues arise | Standard requirement |
| Reference interviews | Limited / records-based | Extensive personal interviews |
| Coverage period | 5-7 years typical | 10 years typical |
| Reinvestigation | Every 10 years | Every 5 years |
| Former name | NACLC | SSBI |
Tier 3 Investigation
Tier 3 is the standard investigation for Secret clearances[1]:
Components include:
- National agency database checks
- Credit bureau checks
- Criminal history records
- Employment verification
- Education verification
- Citizenship verification
Does not typically include:
- Personal subject interview (unless issues found)
- In-person reference interviews
- Neighborhood canvassing
Tier 3 investigations rely more heavily on records checks than personal interviews.
Tier 5 Investigation
Tier 5 is the comprehensive investigation for Top Secret[3]:
Includes all Tier 3 components plus:
- Personal subject interview with investigator
- Interviews with references you provide
- Interviews with developed references (people investigators find)
- Neighborhood interviews at current and past residences
- Detailed foreign contact/travel exploration
- Employment supervisor interviews
Tier 5 investigations are more thorough and take longer to complete.
Processing Times
DCSA publishes average processing times[2]:
Investigation timelines vary based on:
- Complexity of your background
- Number of foreign connections
- Availability of references
- Investigator workload
- Completeness of your SF-86
Tier 5 investigations generally take longer than Tier 3 due to the additional field work required.
What to Expect
During a Tier 3:
- Minimal direct contact
- May receive calls to verify information
- Credit check will appear on your report
During a Tier 5:
- Investigator will contact you for interview
- References will be contacted
- Neighbors may be interviewed
- More extensive documentation review
Other Tiers
The tier system includes other levels[4]:
| Tier | Purpose |
|---|---|
| Tier 1 | Low-risk public trust positions |
| Tier 2 | Moderate-risk public trust positions |
| Tier 3 | Secret / Confidential national security |
| Tier 4 | High-risk public trust positions |
| Tier 5 | Top Secret / SCI national security |
Tiers 1, 2, and 4 are for suitability determinations rather than security clearances.
Continuous Evaluation
Both Tier 3 and Tier 5 clearances are now subject to continuous evaluation, which supplements periodic reinvestigations with ongoing automated record checks.
Related
References
- ^ Investigations & Clearance Process. Defense Counterintelligence and Security Agency. Accessed 2026-01-10.
- ^ DCSA Personnel Vetting Processing Times. Defense Counterintelligence and Security Agency. Accessed 2026-01-08.
- ^ Security Clearance Process: Answers to Frequently Asked Questions. Congressional Research Service. Accessed 2026-01-10.
- ^ DoDI 5200.02: DoD Personnel Security Program. Department of Defense. Accessed 2026-01-08.