Theresa Grennan
Treasurer

Appointed 2025

Democrat

Phone:  (815) 319-4400

Software:  Devnet

Population:  288,542

Zone:  IV

Welcome to Winnebago County, Illinois. 

Office Hours:

• Property Taxes...........Monday - Friday 8:00 - 5:00.

Holiday Closings:

January 1, 2017

December 24, 2017

December 25, 2017

December 31, 2017

Contact Information:

• Property Tax..............(815) 319-4400
• Fax.............................(815) 319-4401
• Email.......................... sgoral@wincoil.us
• County Website...........
• Office Staff
  • Tax Deputy...........................Elmira Nammonds

Our Location:

Winnebago County Treasurer’s Office
404 Elm Street, Room 205
Rockford, IL 61101