The first workers’ compensation check usually arrives with no explanation attached. There is an amount, a date range, and nothing that tells you how the insurance company reached that figure. For many injured workers the number looks too small, and that suspicion is often correct. The weekly payments while you are off work and the value of any permanent disability are both calculated from a single figure called the average weekly wage. Medical benefits are handled separately, and a few benefits are measured differently, but that one number sets most of what the insurance company owes you — and if it is too low at the outset, the error repeats in every payment that follows.
The Starting Point: Your Earnings in the 52 Weeks Before the Injury
Section 10 of the Illinois Workers’ Compensation Act, found at 820 ILCS 305/10, sets out the formula. The average weekly wage means your actual earnings in the job you were working at the time of the injury, measured over the 52 weeks ending with the last day of your last full pay period before the date of injury, divided by 52.
Two details carry weight. The period ends with your last full pay period, not the date of the accident. And the calculation looks only at the job you were in when you were hurt, so earnings from a job you left eight months earlier generally do not count.
The Act then adds an adjustment for lost time. If you lost five or more calendar days during the 52-week period, whether or not those days fell in the same week, the earnings for the remainder are divided by the number of weeks and partial weeks left after the lost time is deducted. The Illinois Supreme Court addressed how that denominator works in Sylvester v. Industrial Comm’n, 197 Ill. 2d 225 (2001). The qualifier the cases apply is that the days must have been lost through no fault of your own — a plant shutdown, a seasonal layoff, a lack of available work. That standard is broader than it sounds, so do not assume an absence is disqualified simply because the reason was personal.
The adjustment is not automatic. You have to prove the days you missed and the length of your normal workweek, and there is no presumption that everyone works forty hours. Absent that proof, a carrier can divide a full year of gross wages by 52 and produce a figure well below what the law allows.
Why This One Number Drives Your Benefits
For most benefits, the Act simply applies a fixed percentage to the average weekly wage.
Temporary total disability benefits equal two-thirds of your average weekly wage under Section 8(b)(1). These are the payments you receive while unable to work — commonly when a doctor takes you off duty, but also when you have restrictions and the employer has no work within them. Permanent partial disability for a scheduled loss or a person-as-a-whole award, and compensation for disfigurement, are paid at sixty percent under Section 8(b)(2.1).
One important benefit does not work that way. If your injury prevents you from returning to your prior occupation and you must take lower-paying work, Section 8(d)(1) provides a wage differential award equal to two-thirds of the difference between what you would be able to earn in the full performance of your old job and what you earn or are able to earn afterward. That first figure is what your old job would pay you now, not necessarily the average weekly wage from the year before your accident — a distinction that matters if wages in your trade rose while your case was pending. For injuries on or after September 1, 2011, a wage differential award runs only until you reach age 67 or five years from the date the award becomes final, whichever is later.
A floor and a ceiling apply. Section 8(b) sets a minimum of two-thirds of forty hours at the higher of the federal or Illinois minimum wage. A spouse and each child raise that percentage by ten points, not the dollar figure by ten percent, though the increase can never push your rate above your own average weekly wage. At the top, the Act caps weekly compensation by reference to the statewide average weekly wage, with a higher cap for temporary total disability, permanent total disability, death benefits, and certain amputations. The Commission publishes the current rates, some of which change twice a year and some annually.
The arithmetic matters. Where your rate falls between the minimum and the maximum, a one-hundred-dollar error in the average weekly wage costs you roughly sixty-seven dollars a week — more than three thousand dollars over a year off work. A settlement is negotiated rather than calculated, but the wage figure drives the exposure the negotiation is built around, so understanding how workers’ compensation settlements are valued in Illinois starts with confirming that number is right.
Overtime and Other Pay Carriers Leave Out
Section 10 says the calculation excludes overtime and bonus. Read alone, that suggests neither ever counts. Illinois courts have drawn finer lines, and the difference is worth real money.
In Tower Automotive v. Illinois Workers’ Compensation Comm’n, 407 Ill. App. 3d 427 (2011), the Appellate Court held that hours worked beyond an employee’s regular weekly hours must be included — at the straight-time rate rather than the premium rate — if those hours were consistent or required as a condition of employment. The benchmark is the hours you regularly worked, not forty. The worker in Tower could be disciplined for refusing overtime, so it counted even though his hours varied. Arcelor Mittal Steel v. Illinois Workers’ Compensation Comm’n, 2011 IL App (1st) 102180WC, drew the same line, counting mandatory scheduled overtime while excluding hours the worker volunteered for.
The opposite result followed in Airborne Express v. Illinois Workers’ Compensation Comm’n, 372 Ill. App. 3d 549 (2007), where the Appellate Court reversed the Commission and excluded overtime because the worker had enough seniority to decline it and could not show it was required. Proving overtime was mandatory is usually the stronger path; proving it was merely consistent is harder, since courts have required both near-weekly overtime and a fairly steady number of hours. Posted schedules, union contract language, and disciplinary policies are what decide the question, and none of it reaches your file on its own.
The word “bonus” is narrower than it sounds as well. A true bonus is something beyond what you were already owed, so pay you were contractually entitled to for production or performance is generally wages. Commissions, documented tips, and vacation and holiday pay have also been counted in appropriate cases.
Short Employment and the Second Job Question
If you had worked for the employer less than a year, Section 10 directs that your earnings be divided by the number of weeks and partial weeks in which you actually earned wages. Only where the shortness of the time or the casual nature of the work makes that impractical does the Act look to what a comparable employee doing the same work for the same hours would have earned — and that impracticality is a real prerequisite, not simply an alternative a party may prefer.
Section 10 also addresses concurrent employment. If you were working two jobs and the employer responsible for your claim knew of that other employment before your injury, wages from both are combined. Those two conditions are what the statute requires, though courts also weigh how regular the second job was and whether the relationship was genuinely ongoing. You carry the burden of proving the employer knew, and having held the job for years is not enough on its own. In Bagwell v. Illinois Workers’ Compensation Comm’n, 84 N.E.3d 1149 (4th Dist. 2017), the court excluded a claimant’s earnings as a pastor because the employer did not know he was paid rather than volunteering. What matters is that the employer understood the work to be paid employment, not that it knew the amount. Earnings from each employer are calculated separately and then added, which matters when you held the jobs for different lengths of time.
What to Do If You Believe the Number Is Wrong
Ask for the wage records used to build the figure. Employers do not always volunteer them, and they may require a formal request, discovery, or a subpoena, but the calculation cannot be checked without them. Compare the records against your pay stubs and look for missing overtime, weeks of lost time that should have reduced the divisor, incentive pay or commissions treated as a bonus, wages paid after your injury for work performed before it, and any second job left out.
Timing matters. When a case is tried, the average weekly wage is typically the subject of a stipulation on the Request for Hearing form, and the parties are generally held to what they stipulate — a strong reason to resolve the question early rather than assuming it can be fixed later. Whether the dispute concerns the weekly benefits you receive while off work or a permanent wage loss award because you cannot return to your old occupation, the wage figure is where the analysis begins.
If your weekly checks do not match what you were earning, the attorneys at The Law Offices of Millon & Peskin, Ltd. can review your wage records and determine whether your average weekly wage was calculated correctly. We represent injured workers throughout the Chicagoland area, including DuPage, Cook, Will, Kane, and Lake counties. Call 630-449-3884 or learn how our firm represents injured workers in Illinois workers’ compensation claims to schedule a free consultation.