If your employer hasn't paid your final wages, this page lays out exactly what Illinois law requires, what it costs your employer to ignore it, and how a properly cited demand letter invokes both. Every deadline, penalty, and citation below was verified against the current statute text or official state guidance.

Illinois's final paycheck deadlines at a glance

If you were fired or laid off At separation if possible; no later than the next regularly scheduled payday
If you quit Same one rule (fired, quit, laid off identical)
The penalty for nonpayment 5% of the underpayment PER MONTH until paid (60%/yr); post-IDOL-order: 1%/day to the employee + 20% to the Department + $250–$1,000 fee

When your final paycheck is due in Illinois

One rule for every separation: final compensation is due at separation if possible, and no later than the next regularly scheduled payday (820 ILCS 115/5, confirmed by the Illinois DOL's own FAQ).

What late payment costs your employer

The 5%-per-month meter: the employee recovers the underpayment plus damages of 5% of the amount per month, continuing until paid (820 ILCS 115/14(a), raised from 2% in 2021) — 60% a year. If the employer ignores an IDOL demand or order, it adds a non-waivable $250–$1,000 administrative fee, a 20% penalty to the Department, and 1% PER DAY to the employee for noncompliance beyond 15 days. Attorney's fees are recoverable in civil suits.

Why the demand letter matters in Illinois

PERSONAL LIABILITY IS THE PRESSURE POINT — officers and agents who knowingly permit the violation are individually liable (§ 115/13). The letter is addressed to the decision-maker BY NAME, making their personal exposure explicit.

Vacation and PTO in the final check

MANDATORY — "final compensation" statutorily includes the cash value of earned VACATION and holidays (§ 115/2). Illinois mandates vacation payout.

Time limit

1 year to file with IDOL (§ 115/11).

What a strong Illinois demand letter looks like

An effective Illinois letter does the following: name the officer; recite the 5%/month meter with the user's actual figures; include the release trap (accepting a disputed check is NOT a release, and conditional endorsements are void); fold earned vacation into the principal. Here's how the opening of a strong one reads:

Free: see this letter with your numbers

Runs in your browser — nothing is sent or stored. Preview only; the full letter is customized to your complete situation.

Illinois Final Paycheck Demand — Preview
[Your Name] [Your Address] [City, IL ZIP] [Date] [Employer Name] [Employer Address] RE: Demand for Payment of Unpaid Final Wages — 820 ILCS 115 Dear [Employer Name], This letter is not a request. It is formal notice. I demand payment of my unpaid final wages in the amount of $[AMOUNT], earned through my last day of work on [LAST DAY WORKED]. Under 820 ILCS 115, my final wages were due as follows: at separation if possible; no later than the next regularly scheduled payday. As of today, [NUMBER] days have passed without payment. Be advised of your exposure under Illinois law for continued nonpayment: 5% of the underpayment PER MONTH until paid (60%/yr); post-IDOL-order: 1%/day to the employee + 20% to the Department + $250–$1,000 fee... Accordingly, demand is hereby made for payment of $[AMOUNT], together with all amounts the law allows, within ten (10) days of the date of this letter — no later than [RESPONSE DEADLINE]. If payment is not received by that date, I will pursue every remedy available under law without further notice. I would prefer to resolve this without litigation — but I am fully prepared to proceed. Govern yourself accordingly, [Your Name]

This preview stops here on purpose. Your complete, court-ready letter — with the 820 ILCS 115 penalty computation and the escalation warnings tailored to Illinois — generates in 60 seconds.

Get My Complete Letter — $9

Need more? Bundle of 3 — $19  ·  Family Pack — $39

Our guarantee: not happy with your letter? We’ll regenerate it or refund it — email support@writemydispute.com.

Primary sources

labor.illinois.gov/faqs/wage-payment-faq.html
codes.findlaw.com/il/chapter-820-employment/il-st-sect-820-115-14/

This guide is general information about Illinois law, not legal advice. Statutes are paraphrased; verify current law for your situation. For significant or contested claims, consult a licensed Illinois attorney.