When you start your application, you must select what type of vendor:

There are two types of vendors that do business with NCDOT:
Contractors -- perform construction or maintenance on transportation facilities, including highways, airports, ferries, etc,
Central-Let Contracts (Prime Bidder)
May bid on Central Let projects that can exceed $5 million. You also are granted POC and a Subcontractor status with this option.
Division-Let Contracts (Purchase Order Contractor)
May bid on Division Let projects under $5 million. You are also granted Subcontractor status with this option.
Subcontractor Works under the direction of the Prime or PO Contractor.
Private Engineering Firms (PEF) -- perform services such as engineering design, research, studies, etc.
Private Engineering Firms (PEF)
May submit Letter of Interest (LOI) for advertisements.
Note: Small Business Enterprise contracts do not require prequalification, but do require SBE certification to bid.
For more information:
SBE certification guidelines.