What NAICS 237310 Covers
NAICS 237310 is the code for Highway, Street, and Bridge Construction. Contractors under this code build and repair roads, highways, bridges, tunnels, overpasses, and airport runways. The work spans site preparation, grading, paving, drainage installation, guardrails, and bridge deck replacement.
Federal buyers use this code for direct construction awards and subcontracting under federally funded state transportation programs. The distinction matters: most of the money flows through state DOTs, not directly from federal agencies, but federal law attaches DBE requirements to every dollar.
Sub-specialties that fall under 237310 include: - Asphalt and concrete paving - Bridge rehabilitation and deck replacement - Intersection reconstruction - Airport apron and taxiway construction - Bike lanes and pedestrian infrastructure built under transportation funding
If you build or repair transportation infrastructure, this is your primary NAICS code.
Federal and FHWA Spend: The Numbers
Direct federal spending under NAICS 237310 runs roughly $4–5 billion per year through agencies like the Army Corps of Engineers, GSA, and the Department of Defense (military road and airfield work). That number understates the real opportunity.
The larger pool is FHWA-funded state transportation contracts. The Bipartisan Infrastructure Law (BIL), signed in November 2021, allocated $110 billion for roads and bridges over five years—roughly $22 billion per year. Combined with pre-existing FHWA formula funding, states are spending $60 billion or more annually on transportation construction. Every federally funded dollar carries a DBE participation requirement, typically set at 10–20% of contract value depending on the state and project type.
That DBE mandate is your entry point. It means prime contractors on large highway jobs are legally required to find and hire certified DBE subcontractors. The demand for qualified DBE firms in this NAICS is not manufactured by goodwill—it is baked into federal law under 49 CFR Part 26.
Spending trend: BIL funding has been accelerating state DOT project pipelines since 2022 and runs through 2026. States like Texas, California, Florida, Ohio, and New York are running some of the largest highway programs in U.S. history right now. This is the best five-year window in a generation for highway construction subcontractors.
Set-Asides and Certifications That Create Competitive Advantage
For direct federal contracts, the most active set-aside categories under 237310 are:
8(a) Business Development: SBA's 8(a) program allows sole-source awards up to $4.5 million for construction. The Army Corps of Engineers and GSA Public Buildings Service use 8(a) set-asides for smaller road and parking structure projects on federal property. If you are an 8(a) firm, you can be awarded contracts without competition in this range.
HUBZone: Many rural highway corridors run through HUBZone-designated areas. If your principal office is in a HUBZone and 35% of employees live in a HUBZone, you qualify. HUBZone set-asides and sole-source awards (up to $4.5M for construction) are available.
SDVOSB: Service-Disabled Veteran-Owned Small Businesses can compete for set-asides on DoD construction work. Military airfield repairs, base road reconstruction, and on-post infrastructure fall here. VA also awards construction contracts with SDVOSB preferences.
WOSB: WOSB set-asides apply in this NAICS. The SBA has designated 237310 as underrepresented for women, meaning contracting officers can use WOSB set-asides here without a market research waiver. This is a direct competitive advantage.
For FHWA-funded state work, the relevant certification is the DBE (Disadvantaged Business Enterprise) certification issued by your state's DOT or a Unified Certification Program (UCP) partner. DBE certification is not the same as 8(a). It is administered state by state, and a certificate from Texas does not automatically apply in California—though some states have reciprocity agreements.
NMSDC MBE certification and WBENC WBE certification do not satisfy DBE requirements on federally funded transportation contracts. The DBE program is separate and specifically governed by USDOT. Get the right credential for the market you are targeting.
SBA Size Standard
For NAICS 237310, the SBA size standard is $45 million in annual receipts (as of the 2022 update). This is a revenue-based standard, not employee count. A firm averaging $45M or less in annual revenue over the past three years qualifies as a small business for federal contracting purposes.
Most subcontractors working under prime contractors on state DOT projects are well under $10M in revenue. You do not need to be large to compete—you need to be certified, bonded, and prequalified.
Contract Vehicles and Where to Find Work
Direct federal contracts are searchable on beta.SAM.gov. Filter by NAICS 237310, set-aside type, and awarding agency. Army Corps of Engineers districts post construction solicitations here, as does the Air Force Civil Engineer Center (AFCEC) for airfield work.
State DOT procurement portals are where the volume is. Every state DOT runs a construction procurement portal separate from SAM.gov. In Texas, it is TxDOT's Let Results system. In California, it is Caltrans' Division of Construction bidding portal. These are not on SAM.gov. You need to register in each state's system separately.
GSA Multiple Award Schedule (MAS): GSA Schedule 03FAC (Facilities Maintenance and Management) and Schedule JanSA include construction-related SINs. NAICS 237310 work appears under SIN 03FAC-6. If federal agencies want to use Schedule vehicles for paving or parking lot reconstruction on federal property, this is the pathway.
IDIQ and MATOC vehicles: The Army Corps of Engineers uses Multiple Award Task Order Contracts (MATOCs) for construction in each of its districts. These are competed periodically, and task orders flow from the pool for years afterward. Winning a MATOC spot is a significant milestone—task orders can flow for 5 to 10 years without rebidding the base contract. Watch the Corps' district websites and SAM.gov for new MATOC competitions.
USDOT OSDBU: The U.S. Department of Transportation's Office of Small and Disadvantaged Business Utilization maintains a resource center specifically for small and diverse firms seeking FHWA-funded work. They publish small business transportation subcontracting lists and connect DBE firms with prime contractors. Start there if you are new to this market.
How to Find Active Solicitations
- beta.SAM.gov: Go to Contract Opportunities. Filter by NAICS 237310. Set award type to "Solicitation." Filter by set-aside type relevant to your certifications. Sign up for email alerts so new postings arrive in your inbox the day they drop.
- State DOT portals: Register on your state DOT's bidding system. Most state DOTs publish a monthly or quarterly "letting schedule" listing upcoming projects and their DBE goals. Review letting schedules 60–90 days out to prepare bids.
- USASpending.gov: Look at past awards under NAICS 237310 in your state. Identify which prime contractors won large FHWA-funded jobs in the past 12 months. Those primes are required to have DBE participation plans. Contact their subcontracting coordinators directly.
- Agency forecast portals: The Army Corps of Engineers publishes annual construction forecasts by district. GSA posts its construction pipeline in the Forecast of Contracting Opportunities. These are worth bookmarking and reviewing quarterly.
What a First Contract Actually Looks Like
For most new entrants, the first contract under NAICS 237310 is a subcontract on a state DOT project, not a direct federal prime contract. Here is the realistic path.
You get DBE-certified by your state UCP (allow 60–90 days for processing). You get bonded—most DOT prime contractors require subcontractors to carry performance and payment bonds or produce consent of surety on jobs above $150,000. You register in your state DOT's bidding portal and in SAM.gov (required for any federal prime work). You build a short capability statement documenting your equipment, past projects, bonding capacity, and certifications.
Then you identify the top 10 prime contractors winning FHWA-funded highway work in your region. You call their DBE or subcontracting coordinator—not their general estimating desk—introduce yourself, and ask to be added to their subcontractor solicitation list. When they bid a project with a 15% DBE goal, they need to find certified firms. You want to be the firm they already know.
The first job is typically paving a specific section, installing drainage pipe, placing guardrails, or handling traffic control. Dollar value: $200K–$1M, depending on project size. Margin on subcontract work in highway construction runs 8–15% if you own your equipment and manage crews efficiently. A $500K subcontract with 10% margin is $50K, and it builds your past performance record for larger work.
After two to three subcontracts, you have the past performance documentation to pursue prime contracts on smaller set-aside jobs—8(a) sole-source awards, SDVOSB set-asides on DoD work, or HUBZone prime bids. The sequence matters. You do not skip straight to priming a $10M bridge job without a record.
Key Steps Before You Pursue Work
- Confirm your SAM.gov registration is active and your NAICS 237310 is listed
- Get DBE-certified through your state UCP if you plan to work on FHWA-funded projects
- Obtain SBA 8(a), HUBZone, WOSB, or SDVOSB certification depending on your ownership profile
- Secure bonding capacity from a surety company—start by calling a bonding agent, not your general insurer
- Contact USDOT OSDBU (1-800-532-1169) to access their small business transportation resources
- Review your state DOT's current DBE program overall goal (published annually on the state DOT website) to understand demand volume
The infrastructure spend window under BIL closes around 2026–2027 as appropriations wind down. Firms that get certified, bonded, and onto prime contractor subcontractor lists in the next 12 months are positioned to capture work during the highest-activity period.
