Illinois has 5 locations with their own GSA per diem rates for FY2026. The highest lodging allowances apply to seasonal destinations such as Chicago, where rates climb in peak months, while East St. Louis / O'Fallon / Fairview Heights, Oak Brook Terrace and Bolingbrook / Romeoville / Lemont have their own year-round rates. Locations not listed by the GSA use the standard CONUS rate of $110 for lodging and $68 for meals and incidental expenses (M&IE).
Use the table below to compare per diem rates across Illinois and calculate the total allowance for your trip.
Illinois per diem rates by city
Cities with their own GSA rate for FY2026, highest lodging first. Seasonal cities show their range. Anywhere not listed defaults to the CONUS standard of $110 lodging / $68 M&IE.
| City / area | Lodging / night | M&IE / day |
|---|---|---|
| Chicago | $142–$234 | $92 |
| East St. Louis / O'Fallon / Fairview Heights | $150 | $86 |
| Oak Brook Terrace | $115 | $80 |
| Bolingbrook / Romeoville / Lemont | $114 | $74 |
| All other Illinois locations (CONUS standard) | $110 | $68 |
Calculate a Illinois trip
Pick any city and your dates to total the lodging + M&IE per diem, including the first/last-day 75% rule.
Frequently asked questions
What is the per diem rate for Illinois in 2026?＋
Illinois has 5 GSA-listed cities with their own rates (up to $234 lodging). Everywhere else in Illinois uses the CONUS standard of $110 lodging and $68 M&IE.
What is the standard per diem rate in Illinois?＋
Cities without a specific GSA rate use the FY2026 CONUS standard: $110 for lodging and $68 for meals & incidentals per day.
Is per diem taxable in Illinois?＋
No — reimbursement at or below the GSA rate under an accountable plan is not taxable to the employee anywhere in the U.S., including Illinois.