Which wage determination applies to my project in Williamson County?

The wage determination incorporated into your contract is the one that governs, per 29 CFR 1.6. For new building work in Williamson County, IL, the current active determination is IL20260002. Verify with your contracting officer before bidding or paying.

How often do these rates change?

DOL publishes wage determination modifications weekly, generally on Fridays. The determination behind this page was last modified May 18, 2026.

What is the difference between the base rate and the fringe rate?

The base rate is the minimum hourly wage; the fringe amount is an additional hourly benefit obligation you can meet with bona fide benefit contributions or pay in cash. On this schedule the median fringe is about 67% of base.

My classification is not listed for Williamson County. What do I do?

If the work classification you need is not on the determination, the contractor requests a conformance (additional classification and rate) through the contracting agency using Standard Form 1444. Do not substitute a similar-sounding classification.

What counts as building construction?

Building covers sheltered enclosures with walk-in access, such as offices, schools, and warehouses, including incidental site work. Single-family and low-rise residential work uses the residential schedule instead.

Does the federal rate or the Illinois state prevailing wage apply?

They are separate systems. Davis-Bacon rates apply to federally funded or assisted work; a state prevailing wage law can apply to state-funded work. A project can be covered by both, in which case the higher rate for each classification effectively controls. This page shows the federal determination only.

Is the WH-347 form mandatory?

The WH-347 itself is optional; what is mandatory on covered work is submitting weekly certified payroll with the same information and a signed Statement of Compliance. Most contractors use the WH-347 layout because agencies expect it.

PREVAILWAGE

Pulling the rate table…

Building prevailing wage rates for Williamson County, IL | PrevailWage

Building prevailing wage rates for Williamson County, IL

ELEVATOR MECHANIC leads the building schedule for Williamson County, IL at $62.73 base plus $38.44 fringe. The active federal wage determination covering building construction in Williamson County, IL lists 196 classifications with published rates, base pay from $22.50 to $62.73 per hour. The determination was last modified May 18, 2026.

Classifications: 196; with published rates
Median base: $38.21; per hour
Median fringe: 67%; of base pay
Last modified: May 18, 2026

Published rates

Classification	Base	Fringe	WD
ASBESTOS WORKER/HEAT & FROST INSULATORINCLUDES APPLICATION OF ALL INSULATING MATERIALS PROTECTIVE COVERINGS, COATINGS AND FINISHINGS TO ALL TYPES OF MECHANCIAL SYSTEMS (CHAMPAIGN, CLARK, DOUGLAS, EDGAR, AND VERMILION COUNTIES)	$40.20	$26.78	IL20260002
ASBESTOS WORKER/INSULATOR(INCLUDES THE APPLICATION OF ALL INSULATING MATERIALS, PROTECTIVE COVERINGS, COATINGS, AND FINISHES TO ALL TYPES OF MECHANICAL SYSTEMS)	$55.02	$35.75	IL20260002
ASBESTOS WORKER/INSULATORINCLUDES THE APPLICATION OF ALL INSULATING MATERIALS; PROTECTIVE COVERINGS, COATINGS, AND FINISHINGS TO ALL TYPES OF MECHANICAL SYSTEMS (FORD AND IROQUOIS COUNTIES)	$55.02

This schedule has been stable recently; the last modification is dated May 18, 2026. Stability is not permanence: annual editions and mid-year modifications can reset rates in Williamson County without local notice.

With 196 classifications carrying published rates, this is a comparatively deep schedule; most trades a building project needs appear without a conformance request.

100% of the rate lines here carry union local identifiers, so the published figures track negotiated agreements, which is why some classifications carry high fringe amounts relative to base.

Using these rates

Read the modification number

A wage determination is cited as number plus modification, for example IL20260002 Mod dated May 18, 2026. Your certified payroll should reflect the determination in your contract, not necessarily the newest one.

Put the WD in your bid file

Save the full determination text with your bid papers the day you price the job. If rates change later, the contract determination is your record of what you bid against.

Match classifications by duties, not titles

The classification that applies is determined by the work performed, not the worker's title. A foreman who works with the tools is generally due the rate for the hours on the tools.

Fringe crediting basics

You can meet the fringe obligation with bona fide benefit plan contributions, cash, or a combination. Track the hourly equivalent of what you contribute; agencies ask for the math.

Statement of Compliance wording

The signed Statement of Compliance may be the WH-347 back page or another document with identical wording. The signature is a federal certification by your company's officer; accuracy is on the certifier.

Use last-4 SSN only

Certified payroll uses the employee's name and an individually identifying number, normally the last four digits of the Social Security number. Full SSNs do not belong on submitted payrolls.

Questions

Which wage determination applies to my project in Williamson County?: The wage determination incorporated into your contract is the one that governs, per 29 CFR 1.6. For new building work in Williamson County, IL, the current active determination is IL20260002. Verify with your contracting officer before bidding or paying.
How often do these rates change?: DOL publishes wage determination modifications weekly, generally on Fridays. The determination behind this page was last modified May 18, 2026.
What is the difference between the base rate and the fringe rate?: The base rate is the minimum hourly wage; the fringe amount is an additional hourly benefit obligation you can meet with bona fide benefit contributions or pay in cash. On this schedule the median fringe is about 67% of base.
My classification is not listed for Williamson County. What do I do?: If the work classification you need is not on the determination, the contractor requests a conformance (additional classification and rate) through the contracting agency using Standard Form 1444. Do not substitute a similar-sounding classification.
What counts as building construction?: Building covers sheltered enclosures with walk-in access, such as offices, schools, and warehouses, including incidental site work. Single-family and low-rise residential work uses the residential schedule instead.
Does the federal rate or the Illinois state prevailing wage apply?

Sources

IL20260002 rev. 4 · modified May 18, 2026

Synced from SAM.gov July 18, 2026. The wage determination incorporated into your contract is the legally operative document.