Calculate Illinois’s per diem rate based on GSA guidelines to simplify your business travels.
For companies operating in Illinois, a well-defined per diem policy is a key tool for managing the costs of this travel in a legally compliant way.
This guide is designed to bring clarity to that process. We'll explore the official GSA per diem rates for Illinois, explain the state's important laws on employee expense reimbursement, and show you how to streamline your system for efficiency and control.
Per diem rates for official travel in Illinois are set by the U.S. General Services Administration (GSA). These federal rates are mandatory for federal employees and serve as a common benchmark for private sector companies looking to create an IRS-compliant reimbursement policy.
For Fiscal Year 2025 (October 1, 2024, to September 30, 2025), key rates are broken down as follows:
The state's primary business and tourism hub, the Chicago metro area, has some of the highest and most seasonally-variable rates in the country.
The first and last day of travel, the M&IE rate is $69.00 for Chicago and $60.00 for Oak Brook Terrace.
For any county in Illinois not specifically listed by the GSA—including other major cities like Springfield (Sangamon County) or Champaign-Urbana (Champaign County)—the standard CONUS rate applies. For FY 2025, this rate is $178 ($110 for lodging and $68 for M&IE).
Find the exact per diem allowance for your business trip to Illinois with our easy-to-use calculator. Select the fiscal year, choose your destination, and input your travel dates. The tool will instantly provide the correct lodging and M&IE rates based on the official GSA schedule.
Illinois has robust laws that protect employees from bearing the costs of business-related expenses.
It's crucial for Illinois employers to understand how the state's legal mandate interacts with the federal per diem system.
In a state like Illinois where expense reimbursement is a legal requirement, maintaining a compliant, accurate, and efficient system is paramount. Fyle’s expense management software automates the entire process, providing an ironclad audit trail while making it simple for employees to get reimbursed quickly.
Here’s how Fyle helps you build a compliant and efficient expense process in Illinois:
With Fyle, you can confidently meet your legal reimbursement obligations in Illinois, giving your finance team powerful controls while offering a simple, modern experience for your employees.
The content on this page is for informational use. As legal standards and per diem rates are subject to change, users should verify current details with official GSA or government resources. This information does not serve as financial or legal counsel.
