Moving in or out mid-month in Chicago? Enter your monthly rent and date to calculate exactly what you owe for a partial month, with Illinois deposit and notice rules for 2026.
Last updated: May 2026 · Data: MIT Living Wage Calculator, C2ER, U.S. Census, BLS, IRS, state and city sources
Prorated rent is what you pay for a partial month when you move in or out on a day other than the first. With average Chicago rent near $1,900/month, the standard method divides monthly rent by the days in the month and multiplies by days occupied. Illinois sets no statewide cap on security deposits, though local ordinances in Chicago and elsewhere add their own rules. Under the state Security Deposit Return Act, landlords of larger buildings must return the deposit, with an itemized statement of deductions, generally within 30 to 45 days of move-out. A 30-day written notice generally ends a month-to-month tenancy.
| Rule (Illinois) | Detail |
|---|---|
| Average 1-bedroom rent | $1,900/month |
| Average 2-bedroom rent | $2,350/month |
| Security deposit limit | no statutory cap (set by lease or local ordinance) |
| Deposit return deadline | 30 to 45 days after move-out |
| Month-to-month notice | 30 days written notice |
| Standard proration formula | Rent ÷ days in month × days occupied |
Example: rent is $1,900, move-in is the 10th of a 30-day month, so 21 days remain. Prorated rent is ($1,900 ÷ 30) × 21 = $1,330.
Chicago is the third-largest city in the United States and the economic capital of the Midwest, a global hub for derivatives and futures trading (CME and Cboe), corporate headquarters, rail and air transportation through O'Hare, manufacturing, healthcare, and a fast-growing technology sector.
| Local Metric | Chicago (2026 estimate) |
|---|---|
| Metro population | 2.7 million |
| County / jurisdiction | Cook County |
| Cost of living index (US avg = 100) | 116 |
| MIT living wage, single adult | $22.00/hour |
| MIT living wage, one earner supporting a family of four | $43.00/hour |
| Applicable minimum wage | $16.60/hour |
| Average rent, 1-bedroom | $1,900/month |
| Average rent, 2-bedroom | $2,350/month |
| Median home price | $360,000 |
| Median household income | $71,000/year |
| Combined sales tax rate | 10.25% |
| Effective property tax rate | 1.75% of value/year |
Local figures are 2026 estimates compiled from the MIT Living Wage Calculator, the C2ER Cost of Living Index, U.S. Census and Zillow housing data, and city and county sources. Verify current figures before relying on them.
Divide your monthly rent by the number of days in the move-in month, then multiply by the days you occupy the unit. For example, $1,900 rent divided by 30 days times 15 days occupied is $950. Use the calculator above for your dates.
Average rent in Chicago is about $1,900/month for a 1-bedroom and $2,350 for a 2-bedroom, which is why getting proration right matters when you move mid-month.
In Illinois the security deposit limit is no statutory cap (set by lease or local ordinance). The deposit must be returned within 30 to 45 days of move-out with an itemized statement of any deductions. Illinois sets no statewide cap on security deposits, though local ordinances in Chicago and elsewhere add their own rules. Under the state Security Deposit Return Act, landlords of larger buildings must return the deposit, with an itemized statement of deductions, generally within 30 to 45 days of move-out. A 30-day written notice generally ends a month-to-month tenancy.
In Illinois, 30 days of written notice generally ends a month-to-month tenancy, though your lease may require more. Notice timing also affects your final prorated rent.
There is no statute mandating a specific proration method in Illinois, but most landlords prorate as standard practice. Confirm the method in writing in your lease before signing to avoid disputes.