Prevailing Wage Jobs and Your Workers Comp Audit - What Civil Contractors Learn the Hard Way

Author: Grit Insurance Group

You bid a state highway job at prevailing wage. Your normal laborer rate is $22 per hour, but the prevailing wage determination says $38 per hour plus fringe. You won the job. You did the work. Six months later, your workers comp audit comes in and you owe an extra $15,000 you never budgeted for.

You call your agent. "Why is this so high?" The answer is simple math that nobody explained before you signed the contract.

Prevailing wage projects push your reported payroll up. Workers comp premiums are calculated on reported payroll. Higher payroll means higher premium. And most civil contractors do not find out until the audit bill lands on their desk.

This article walks through exactly how it works, shows the math with real numbers, and explains what you can do about it before you bid your next prevailing wage job.

What Is Prevailing Wage and Who Does It Apply To?

Prevailing wage is the minimum hourly rate (including benefits) that contractors must pay workers on publicly funded construction projects. The rate is set by government agencies based on wages typically paid for similar work in the same geographic area.

At the federal level, the Davis-Bacon Act requires prevailing wages on all federal construction contracts over $2,000. That covers highway projects funded through the Federal Highway Administration, Army Corps of Engineers work, federal building construction, and any project receiving federal grants or loans for construction. The Davis-Bacon Act has been in effect since 1931 and its requirements extend to more than 70 related federal statutes, including the Federal-Aid Highway Acts and the Infrastructure Investment and Jobs Act (U.S. Department of Labor - Davis-Bacon and Related Acts).

At the state level, 32 states have their own prevailing wage laws that apply to state-funded and locally funded public works (Points North - Prevailing Wage Laws 2025). Thresholds vary widely. California applies prevailing wage to nearly all public works. Colorado's threshold is $500,000. Wyoming and Nevada set it at $100,000. Some states like Tennessee only apply it to highway construction.

If you are a civil contractor, highway builder, or excavation company doing public work, you are almost certainly working under prevailing wage requirements on a regular basis. And every one of those projects is inflating your workers comp audit.

How Workers Comp Premiums Are Calculated

Before we get to the prevailing wage problem, you need to understand the basic formula your carrier uses to calculate your workers compensation premium:

(Payroll / 100) x Class Code Rate x Experience Modification Factor = Premium

Three pieces drive the number:

• Payroll - Total wages paid to employees in each job classification during the policy period. This is the big one.
• Class code rate - A rate per $100 of payroll assigned to each type of work. Higher-risk work gets a higher rate. Civil and highway work carries some of the higher rates in construction.
• Experience modification factor (e-mod) - Your company's claims history compared to the industry average. A mod of 1.0 is neutral. Below 1.0 means better than average. Above 1.0 means worse.

Common NCCI class codes for civil and highway contractors include:

• 5506 - Street or road paving and resurfacing (rates typically $4.00 to $10.00+ per $100 of payroll depending on state)
• 5507 - Street or road construction, subsurface work (rates typically $4.00 to $7.00+ per $100)
• 6217 - Excavation and drivers (rates typically $3.50 to $5.50+ per $100)
• 6306 - Sewer construction (rates typically $5.00 to $9.00+ per $100)

(Lite Speed Insurance - WC Class Codes and Rates; New York WCB - 2025 Payroll Class Codes)

When your policy starts, the carrier estimates your premium based on projected payroll. At the end of the policy year, they audit your actual payroll. If actual payroll was higher than estimated, you owe the difference. That is the audit bill.

Why Prevailing Wage Blows Up Your Audit

Here is the part that catches contractors off guard.

Under NCCI rules - which govern workers comp in 38 states - "Davis-Bacon wages or wages from a similar prevailing wage law" are explicitly included in the payroll used to calculate workers compensation premium (Veritas Risk Management - NCCI Remuneration Rule; OR Marks - Understanding WC Premium Audits).

That means the full prevailing wage rate your workers earn - not your normal rate - is the number your carrier uses at audit. If prevailing wage doubles your labor rate on a project, your workers comp premium on that labor roughly doubles too.

Most contractors estimate their annual payroll at the start of the policy based on their normal pay rates. They may account for some growth, maybe a few extra hires. But they do not account for the fact that half their crew spent six months earning $38 per hour instead of $22 per hour. When the auditor pulls the payroll records, the actual number is significantly higher than the estimate. And the additional premium bill follows.

The Math - A Real Dollar Example

Let's walk through a scenario every civil contractor will recognize.

Your company: A civil/highway contractor with a 10-person field crew. Your workers comp class code is 5506 (road paving) with a rate of $5.00 per $100 of payroll. Your experience mod is 1.0 (neutral).

Normal pay rates: Your average laborer earns $24 per hour. Working 2,000 hours per year, that is $48,000 in annual payroll per worker. For 10 workers, your total payroll is $480,000.

Estimated annual workers comp premium:

($480,000 / 100) x $5.00 x 1.0 = $24,000

Now let's say your crew spends six months on a state highway project at prevailing wage. The prevailing wage determination sets the rate at $38 per hour base wage plus $12 per hour in fringe benefits.

Prevailing wage payroll for those six months (base wage only):

10 workers x 1,000 hours x $38/hour = $380,000

Normal payroll for the other six months:

10 workers x 1,000 hours x $24/hour = $240,000

Actual annual payroll: $380,000 + $240,000 = $620,000

Actual workers comp premium at audit:

($620,000 / 100) x $5.00 x 1.0 = $31,000

The audit bill: $31,000 - $24,000 = $7,000 additional premium.

And that is a conservative example. If you pay fringe benefits as cash in lieu (directly to the worker instead of into a trust), those dollars get added to reportable payroll too. In this example, that is another $12 per hour x 1,000 hours x 10 workers = $120,000 in additional payroll.

If fringe is paid as cash:

Total actual payroll: $620,000 + $120,000 = $740,000

Actual premium: ($740,000 / 100) x $5.00 x 1.0 = $37,000

Audit bill: $37,000 - $24,000 = $13,000 additional premium.

For a contractor running tight margins on a highway job, $7,000 to $13,000 in unbudgeted cost is real money. And on larger projects with bigger crews and longer timelines, the number climbs fast.

The Fringe Benefit Question - Cash vs. Trust

How you handle the fringe benefit portion of prevailing wage directly affects your workers comp audit.

Paid to a third-party trust or benefit plan: If fringe benefits go into a bona fide health plan, pension fund, vacation trust, or similar third-party fund, that money is typically excluded from workers comp payroll in most NCCI states (ICW Group - Premium Audit Payroll Reporting Instructions). This is the favorable treatment.

Paid as cash in lieu: If you pay the fringe amount directly to the worker as additional hourly wages (cash in lieu of benefits), that becomes reportable payroll. Your carrier charges premium on it. This is the treatment that hurts.

Some contractors default to paying everything as cash because it is simpler. That simplicity costs them at audit. If you are running prevailing wage projects regularly, setting up qualifying benefit plans for your crew can reduce your workers comp exposure significantly. Talk to your agent about structuring fringe payments to keep them off the audit.

The Overtime Angle

There is one small break in the rules. Under NCCI guidelines, the overtime premium portion of pay can be excluded from workers comp payroll in most states. If a worker earns $38 per hour straight time and $57 per hour at time-and-a-half overtime, only the $38 per hour portion is included for the overtime hours - not the full $57 (Alloy Employer Services - Calculating Payroll for a WC Audit).

Note: Pennsylvania and Delaware do not allow the overtime exclusion. If you work in those states, the full overtime rate counts as payroll (ICW Group - Premium Audit Payroll Reporting).

This exclusion helps, but it does not offset the core problem. The straight-time prevailing wage rate is still significantly higher than your normal rate, and that is what drives the audit increase.

How to Stop Getting Surprised

You cannot avoid the higher premium. Prevailing wage payroll is reportable payroll. But you can stop the surprise. Here is how:

1. Budget the Workers Comp Uplift Into Every Prevailing Wage Bid

Before you submit a bid on any prevailing wage project, calculate the workers comp cost at the prevailing wage rate - not your normal rate. The formula is straightforward:

(Prevailing wage hourly rate x estimated hours x number of workers) / 100 x your WC rate x your e-mod = estimated WC cost for that project

Compare that number to what you would pay at normal rates. The difference is your prevailing wage premium uplift. Build it into the bid as a line item.

2. Tell Your Agent About Prevailing Wage Projects

When you win a prevailing wage job, call your agent. Give them the project details, estimated payroll at prevailing wage rates, and expected duration. A good agent will adjust your payroll estimate mid-term so the premium increase is spread across the policy period - not dumped on you in one audit bill.

3. Structure Fringe Benefits to Reduce Reportable Payroll

If you are paying fringe as cash in lieu, you are paying workers comp on that money. Setting up qualifying benefit plans (health, retirement, vacation trusts) lets you route fringe dollars to a third-party fund and keep them off the audit. The savings add up fast on multi-project, multi-year prevailing wage programs.

4. Keep Clean Payroll Records by Project

Your auditor needs to see which hours were worked on prevailing wage projects and which were not. If your records do not separate prevailing wage payroll from normal payroll, you lose the ability to track the impact and plan for it. Your certified payroll reports (WH-347) are a good starting point, but your internal payroll system needs to track this too.

5. Consider Pay-As-You-Go Workers Comp

Pay-as-you-go programs calculate your workers comp premium each pay period based on actual payroll. Instead of one large audit adjustment at year end, your premium adjusts in real time as prevailing wage hours hit the books. This does not reduce the total cost, but it eliminates the cash flow shock of a big audit bill.

Which States Have Prevailing Wage Laws?

If you work on federal projects, Davis-Bacon applies in all 50 states. But 32 states also have their own prevailing wage laws for state-funded and locally funded public works. Thresholds vary (World Population Review - Prevailing Wages by State 2026):

• No threshold or very low: California ($1,000), Rhode Island ($1,000), Hawaii ($2,000), New Jersey ($2,000), Minnesota ($2,500)
• Mid-range: Alaska ($25,000), Montana ($25,000), Pennsylvania ($25,000), Maine ($50,000), Tennessee ($50,000, highway only), New Mexico ($60,000)
• Higher thresholds: Ohio ($75,000), Missouri ($75,000), Nevada ($100,000), Wyoming ($100,000), Virginia ($250,000), Maryland ($250,000), Colorado ($500,000)

Eighteen states do not have state-level prevailing wage laws, though federal Davis-Bacon still applies to federally funded projects in those states. If you are a civil contractor working across state lines, know the prevailing wage landscape before you bid.

The Bottom Line for Civil Contractors

Prevailing wage is not just a payroll issue. It is an insurance cost issue. Every dollar of prevailing wage you pay shows up on your workers comp audit as reportable payroll. Your carrier does not care whether that wage was set by the government or negotiated by you - it is payroll, and they charge premium on it.

The contractors who handle this well are the ones who see it coming. They budget the workers comp uplift into their bids. They tell their agent when they win prevailing wage work. They structure fringe benefits to minimize reportable payroll. And they keep records clean enough that their auditor can process the numbers without guessing.

The contractors who get hurt are the ones who bid a project at prevailing wage, never think about the insurance side, and then get an audit bill that eats the margin they thought they had.

Do not be that contractor.

FAQ - Prevailing Wage and Workers Comp Audits

Does prevailing wage payroll count toward my workers comp premium?

Yes. Under NCCI rules, Davis-Bacon wages and wages from similar state prevailing wage laws are included in the payroll used to calculate your workers compensation premium. The higher hourly rate you pay on prevailing wage projects becomes the reportable payroll your carrier uses at audit. The only portion you can potentially exclude is fringe benefits paid to a qualifying third-party trust or benefit plan.

Can I exclude the fringe benefit portion of prevailing wage from my workers comp audit?

In most states, yes. If you pay the fringe benefit portion into a bona fide third-party benefit plan, trust, or fund (health insurance, pension, vacation fund), that amount can be excluded from your workers comp payroll calculation. However, if you pay fringe benefits as cash directly to the worker, that cash becomes part of reportable payroll and you pay workers comp premium on it. Documentation is critical - your auditor will want to see proof of third-party contributions.

How much more does workers comp cost on prevailing wage jobs?

The increase depends on the gap between your normal pay rate and the prevailing wage rate. If prevailing wage pushes your laborer rate from $22/hour to $38/hour in base wages, your workers comp payroll for that employee increases by roughly 73%. At a workers comp rate of $5.00 per $100 of payroll, that difference can add $1,600 or more per worker over a single project. For a crew of 10 on a six-month highway project, the additional workers comp cost can easily reach $7,000 to $13,000 or more.

What workers comp class codes apply to civil and highway contractors?

Common NCCI class codes for civil and highway work include 5506 (street or road paving and resurfacing), 5507 (street or road construction - subsurface work), 6217 (excavation and drivers), and 6306 (sewer construction). Rates vary by state but typically range from $3.50 to $10.00 or more per $100 of payroll, making these among the higher-rated construction classifications.

How do I budget for the workers comp increase on a prevailing wage project?

Calculate the full prevailing wage rate (base wage plus any cash-in-lieu fringe) for every classification on the project. Multiply that by the hours you expect each classification to work. Apply your workers comp rate per $100 of payroll and your experience modification factor to get the estimated premium for that project. Compare that number to what you would pay at your normal wage rates. The difference is your prevailing wage workers comp premium uplift - and it needs to be a line item in your bid.

Talk to the Grit Team

If you are a civil contractor running prevailing wage work and your workers comp audits keep coming in higher than expected, that is a problem your insurance program should be solving - not creating. The Grit team works with highway contractors, excavation companies, and civil builders across the country to build insurance programs that account for prevailing wage exposure from day one.

We help you structure your workers comp, budget the real cost into your bids, and avoid the audit surprises that eat your margins.

Call us: (801) 505-5500

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Grit Insurance Group is an independent national brokerage specializing in contractor insurance and surety bonding. Prevailing wage requirements, workers comp rates, and audit rules vary by state. Always verify current requirements with your state department of labor and a licensed insurance advisor before making coverage decisions.