This page helps users handle Property Tax tasks in Rock Island County, Illinois, including looking up tax records, checking payment options, and finding the right office for bill or assessment questions.

Use the Rock Island County Property Tax Inquiry for parcel, owner, address, sales, advanced parcel, and mobile home searches. Payment questions are handled through the Rock Island County Treasurer’s Office.

Rock Island County Property Tax Inquiry

The Rock Island County Property Tax Inquiry is the main online tool for searching property tax records. The best search is by Parcel Number as it appears on the tax bill, but the tool also supports owner name and address searches.

  • PIN or Parcel Number, with or without dashes
  • Owner name
  • House number, street name, street type, and city
  • Sale price range or sale date range
  • Township, tax district, property class, or tax year range for advanced searches

The tool also includes a mobile home search by mobile home number, owner name, or site address. Records are for inquiry and review, and automated data retrieval is prohibited.

  • Choose the parcel, advanced parcel, or mobile home search option.
  • Enter at least one search field.
  • Review the matching record and change the tax year if you need current or prior year information.

Prior year tax information can be checked in the Devnet wEdge tool by changing the Tax Year tab; available years go back to 2003.

Real estate tax due dates

For 2025 real estate taxes payable in 2026, Rock Island County lists four installment due dates.

Installment Due date
1st installment Wednesday, June 10, 2026
2nd installment Monday, August 10, 2026
3rd installment Thursday, September 10, 2026
4th installment Tuesday, November 10, 2026

Real estate tax bills are mailed on or before May 1, 2026. Mobile home tax bills are mailed on or before May 8, 2026, and are due Friday, July 10, 2026.

Property tax payment options

Rock Island County provides several payment methods. Installments must be paid in sequence, and partial installment payments are not accepted.

Payment method Key details
Online Use the Rock Island County online payment system for e-check, debit or credit card, or mobile wallet payments. The last day to pay online is Friday, November 13, 2026, at 11:55 pm.
Phone Call (309) 518-9200 to pay by e-check, debit or credit card, or mobile wallet. Phone payments are available in Spanish.
Mail Mail a check or money order with the payment stub to Rock Island County Collector, PO Box 3277, Rock Island, IL 61204-3277. A U.S. postmark on or before the due date is required to avoid penalty.
In person Pay at the Treasurer’s / Collector’s Office at 1504 3rd Avenue, Rock Island, IL 61201. Accepted forms include cash, check, cashier’s check, or money order.
Drive-up drop box Place the payment and stub in an envelope and use the secure box in the alley or parking lot behind the County Office Building.
Local banks and credit unions Participating banks and credit unions accept real estate tax payments through Tuesday, November 10, 2026. Some locations serve members only, and credit or debit cards are not accepted.

Late or final payments: Payments received after Friday, November 13, 2026, must be made by cash, cashier’s check, certified check, or money order. The last day property tax payments are accepted is December 28, 2026.

Online and card payment fees

Online and phone payments use a third-party processor. Processing fees are not charged by the Rock Island County Treasurer’s Office.

Payment type Fee
E-check $1.00 processing fee
Credit or debit card 2.45% processing fee
Mobile wallet 2.45% processing fee
Transactions under $82.00 $2.00 card or mobile wallet processing fee

Individual users are limited to 10 items per online cart transaction. For technical questions about the online payment account or setup, contact the Autoagent Help Desk at 1-877-932-8478 or [email protected].

Escrow, delinquent taxes, and tax sale timing

If a mortgage company is expected to pay the tax bill, the shaded area of each stub may show that information. Property owners are still responsible for confirming that the correct parcel is paid on time and in full.

Use EscrowCheck on the real estate payment page to see whether an escrow payment has been submitted. This can help avoid double payments or missed payments through a lender.

After the fourth installment is due, Rock Island County may send a certified delinquency notice and publish unpaid amounts in the newspaper with an additional $10 fee. Taxes not paid by December 28, 2026, will be sold at the Tax Sale on December 29, 2026.

Assessment search and property tax relief

For assessment details, use the county’s Assessment Search page after agreeing to the disclaimer. Assessment records are public information for inquiry and review purposes only.

Property tax relief questions go through the Chief County Assessment Office or the taxpayer’s Township Assessor. Available forms listed by the county include homestead, senior freeze, disabled persons, disabled veterans, returning veterans, charitable, religious, hospital, open space, and natural disaster exemptions.

Rock Island County Property Tax contacts

Use the Treasurer’s Office for tax bill and payment questions. Use the Assessment Office for assessment and exemption questions.

  • Rock Island County Treasurer’s Office, 1504 Third Avenue, 1st Floor, Rock Island, IL 61201
    Phone: (309) 558-3510
    Fax: (309) 558-3511
    Hours: Monday through Friday, 8 am to 4:30 pm
  • Rock Island County Assessment Office, 1504 Third Avenue, County Office Building, 2nd Floor, Rock Island, IL 61201
    Phone: (309) 558-3660
    Fax: (309) 558-3658
    Hours: Monday through Friday, 8 am to 4:30 pm

Common questions

Where can I look up Rock Island County property tax records?

Use the property tax inquiry tool to search by PIN, owner name, address, sales criteria, advanced parcel criteria, or mobile home information.

Where can I pay Rock Island County property taxes online?

Use the online payment portal. You can search by PIN, owner name, or address, add bills to the cart, and check out as a guest or with an account.

What happens if I miss a due date?

Installments not paid by the due date are subject to interest of 1.5% per month or part of a month until paid, sold, or forfeited.

Can I make a partial installment payment?

No. Rock Island County states that partial installment payments are not accepted. Each installment must be paid in full, including any applicable penalty interest.

Who should I call about a tax bill or payment?

Call the Rock Island County Treasurer’s Office at (309) 558-3510 for questions about tax bills and payments.

Who handles assessment and exemption questions?

The Rock Island County Assessment Office handles assessment information and property tax relief questions. Call (309) 558-3660.