Detailed Answer
NAICS codes and bidding:
**How It Works:**
- Solicitation specifies the NAICS code
- Your size is measured against that code's standard
- You can be "small" for some codes, not others
**Multiple NAICS Registration:**
- Register multiple codes in SAM.gov
- List codes you can legitimately perform
- Don't register codes you can't perform
**Size Determination Per Contract:**
- Size evaluated at time of offer
- Based on solicitation's assigned NAICS
- May be small for one contract, large for another
**Best Practices:**
- Focus on 3-5 core NAICS codes
- Choose primary NAICS carefully
- Keep SAM.gov profile accurate
- Track size against key codes