PREVAILING WAGE OVERHEAD

PREVAILING WAGE OVERHEAD RATE: WHY IT'S DIFFERENT AND HOW TO CALCULATE IT.

QUICK ANSWER

A contractor who uses the same overhead rate for prevailing wage and private work is either overpricing private work or underpricing prevailing wage work. Prevailing wage carries certified payroll administration, fringe benefit compliance, and wage classification overhead that private work doesn't. The correct approach is two overhead rates: a base rate for private work, and a prevailing wage surcharge added to the base for public bids. SPM builds separate overhead rates for clients who do both, and the prevailing wage rate includes all compliance overhead at the correct allocation.

The reason one blended rate fails is that the compliance cost is fixed per project rather than proportional to contract value. Three hours a week of certified payroll work costs the same on a $400K job as on a $1.2M job, so a blended rate overprices the large private jobs and underprices the small public ones. Calculating the surcharge from your own certified payroll hours takes an afternoon, and it settles the question for every bid that follows.

BY JOSH LUEBKERPublished 2026-08-06Updated 2026-08-07
THE DEFINITION

WHAT IT MEANS.

A prevailing wage overhead rate is your base overhead rate plus a surcharge covering the compliance costs only public work creates: certified payroll administration, fringe benefit compliance, and wage classification review.

THE COST STRUCTURE DIFFERENCES

WHY ONE RATE IS WRONG FOR BOTH.

01

The fringe benefit structure

On prevailing wage projects the wage determination specifies a base hourly rate plus a fringe benefit amount per hour, and the fringe covers health insurance, retirement, apprenticeship, and other benefits the determination requires. Contractors can satisfy it by paying cash on top of the base wage, by providing bona fide fringe benefits, or by a combination of both. Either way, the cash fringe payment or the cost of providing bona fide benefits is a direct labor cost on prevailing wage projects that doesn't exist on private work at the same base wage, and it changes the fully burdened labor rate.

02

The certified payroll burden

Prevailing wage projects require certified payroll reports submitted weekly to the awarding agency or the GC. Verifying wage classifications, calculating fringe compliance, producing the reports, and answering compliance inquiries takes 1 to 4 hours per week per prevailing wage project depending on crew size and complexity. At 3 hours per week at $55 an hour for an admin or controller, that's $165 a week, or $8,580 over a 52 week project. That burden is a fixed cost of prevailing wage work and it belongs in the overhead rate for prevailing wage bids.

03

The classification risk

Workers on prevailing wage projects must be classified at the correct wage classification for the work they're performing. A worker doing higher classification work who gets paid at a lower classification rate creates a back pay liability equal to the wage differential for every hour worked at the wrong classification. Wage classification errors on a 6 month project with a 5 person crew are the kind of compliance failure that produces a $30,000 to $80,000 back pay judgment. The administrative overhead of keeping classifications correct is a cost of doing prevailing wage work.

THE ARITHMETIC

WHAT IT LOOKS LIKE IN DOLLARS.

What certified payroll costs per project

Certified payroll administration takes 1 to 4 hours per week per project. At 3 hours per week at $55 an hour for an admin or controller, that's $165 a week, or $8,580 over a 52 week project.

What a classification error costs

Wage classification errors on a 6 month project with a 5 person crew are the kind of compliance failure that produces a $30,000 to $80,000 back pay judgment, because the liability is the wage differential for every hour worked at the wrong classification.

What the surcharge usually comes to

For a contractor running 2 to 3 simultaneous prevailing wage projects, the surcharge typically runs 1.5 to 3.0 points of additional overhead rate. Contractors with higher prevailing wage volume may carry a lower surcharge per project, because the fixed compliance costs spread across more revenue.

THE CALCULATION

TWO RATES, THREE STEPS.

Step one, isolate the prevailing wage only costs

Certified payroll administration time, compliance software or service fees, wage determination monitoring, and classification review are prevailing wage specific overhead costs. Private work carries none of them, which is why they can't sit inside a blended rate and still produce an accurate bid.

Step two, calculate the surcharge

Sum the prevailing wage specific overhead costs and divide by projected prevailing wage revenue. That percentage is the overhead surcharge, and it applies only to prevailing wage bids.

Step three, add it to the base rate for public bids

Base overhead rate plus prevailing wage surcharge equals the overhead rate for prevailing wage bids. Private work bids use only the base overhead rate. Two numbers in the bid template instead of one, and the estimator picks the one that matches the work.

The fringe benefit strategy

Contractors who establish a bona fide fringe benefit plan, whether that's union health and welfare or a qualifying employer sponsored plan, can credit the bona fide fringe cost against the prevailing wage fringe requirement. That reduces the cash fringe payment required on prevailing wage projects and may be more tax efficient than paying the full fringe in cash. SPM coordinates with the CPA on fringe benefit structure for clients who do significant prevailing wage volume.

$10.7M+
Client AR Recovered Since 2023
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Active Trade Specializations
60 DAYS
Average Onboarding Time
PRICING

FLAT MONTHLY FEE. NO SURPRISES.

Three tiers, priced by your trailing twelve month revenue. Which one you're in depends on how much of the work you want off your desk. No hourly billing, no payroll, and no add-ons.

Pricing

Last 12 months revenueMonthly fee
Up to $1M$1,900 to $2,900
$1M to $3.5M$2,600 to $3,900
$3.5M to $6.5M$3,800 to $5,700
$6.5M to $9.5M$5,100 to $7,100
$9.5M to $12.5M$6,100 to $8,500
$12.5M to $15.5M$7,400 to $11,000
$15.5M to $18.5M$9,400 to $13,500
$18.5M+Quoted individually

Range reflects the three tiers below. Which one you're in depends on how much of the work you want off your desk. No payroll. No hidden line items.

Core

You stop guessing.

You get the CFO work. Job costing built against the way you estimate, a 13 week cash forecast, monthly WIP, and a meeting every month that ends in decisions rather than a report.

Your bookkeeper keeps doing the books.

Executive

You stop touching the books.

Everything in Core, and we run the bookkeeping and the controllership as well. Nobody in your office is answering coding questions or chasing a reconciliation at month end.

We do the books. No payroll.

Strategic

Every job shows its margin while it's still running.

Everything in Executive, plus the job costing and WIP platform set up, loaded with your cost codes, and managed for you every month. You never have to learn it.

We do the job costing.

COMMON QUESTIONS

FREQUENTLY ASKED.

The prevailing wage surcharge depends on your certified payroll volume and compliance complexity. For a contractor with 2 to 3 simultaneous prevailing wage projects it typically runs 1.5 to 3.0 points of additional overhead rate. For contractors with higher prevailing wage volume the surcharge may be lower per project, because the fixed compliance costs spread across more revenue. Calculate it from your certified payroll administration hours rather than estimating it.
Yes, if the health insurance plan qualifies as a bona fide fringe benefit under the Davis-Bacon Act. The plan must be genuine rather than illusory and it must provide reasonable benefits, and most employer sponsored health insurance plans qualify. The qualifying fringe credit reduces the cash fringe payment required on prevailing wage projects. The specific credit requires certification with the DOL Wage and Hour Division.
SPM doesn't handle payroll processing, and that includes certified payroll production. SPM does handle the overhead rate structure for prevailing wage work, the cost code structure that separates prevailing wage from private work, and the financial analysis of prevailing wage versus private work margins. Certified payroll production is coordinated with a payroll provider.
Three tiers, and which one you are in depends on how much of the work you want off your desk. Core is where you stop guessing: job costing built against the way you estimate, a 13 week cash forecast, monthly WIP, and a monthly meeting that ends in decisions, while your bookkeeper keeps doing the books. Executive is where you stop touching the books, because we run the bookkeeping and the controllership as well. Strategic is where every job shows its margin while it is still running, because the job costing and WIP platform is set up and managed for you. No payroll. No scope gaps.
Sixty days. We migrate your books back to the start of your last taxable year, set up ControlQore, and build your job costing structure from scratch. Fully operational in two months.
WHAT THIS TIES INTO
Josh Luebker, The Construction CFO
Josh Luebker
FRACTIONAL CFO · THE CONSTRUCTION CFO

Former commercial project manager and master electrician: 150+ projects worth $2.1B combined, from $50,000 to $300M. Now fractional CFO to commercial subcontractors.

DO YOUR PUBLIC AND PRIVATE BIDS CARRY THE SAME OVERHEAD RATE?

Bring last year's certified payroll hours and your bid template. We'll calculate the surcharge with you and tell you which work you've been underpricing.

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