For general information about the County Administrative Offices or County Services, please call (302) 855-7700. To contact a specific department see the list below. For infomation about a department, click the department name.
Options for the Hearing Impaired (free services provided through the Delaware Relay Center):
| Office | Phone | Fax | |
| Accounting | (302) 855-7853 | (302) 855-7722 | Gina Jennings Keith Moore |
| Addressing | (302) 855-1176 | (302) 853-5889 | Megan M. Nehrbas |
| Airport/Industrial Park | (302) 855-7774 | (302) 855-7773 | Jim Hickin |
| Assessment | (302) 855-7824 | (302) 855-7828 | Eddy Parker Chris Keeler |
| Building Code | (302) 855-7860 | (302) 855-7869 | Andy Wright |
| Community Development and Housing |
(302) 855-7777 | (302) 854-5397 | William Lecates |
| Constable | (302) 855-7819 | (302) 855-7828 | Alan Holloway |
| County Administration | (302) 855-7742 | (302) 855-7749 | David Baker |
| County Council | (302) 855-7743 | (302) 855-7749 | Robin Griffith |
| Data Processing | (302) 853-1718 | (302) 855-7845 | Bonnie Smith Deborah Street |
| Economic Development | (302) 855-7770 | (302) 855-7773 | Julie Wheatley |
| Emergency Medical Services |
(302) 854-5050 | (302) 855-7780 | Robert Stuart |
| Emergency Operations Center |
(302) 855-7801 | (302) 855-7805 | Joe Thomas |
| Engineering | (302) 855-7718 | (302) 855-7799 | Michael Izzo Jeff James |
| Environmental Services | (302) 855-7730 | (302) 539-0981 | Heather Sheridan Rodney Marvel |
| Facilities Management | (302) 855-7840 | (302) 855-7749 | Doug Stoakley |
| Finance Administration | (302) 855-7741 | (302) 855-7749 | Susan M. Webb |
| Historic Preservation | (302) 856-6138 | (302) 855-7799 | Dan Parsons |
| Information Technology | (302) 855-7898 | (302) 853-5898 | Thomas Glenn |
| Libraries | (302) 855-7890 | (302) 855-7895 | Carol Fitzgerald |
| Mapping | (302) 855-7827 | (302) 855-7828 | Buddy Lynch |
| Marriage Bureau | (302) 853-1717 | (302) 855-7798 | George Parish |
| Personnel | (302) 855-7711 | (302) 855-7715 | Dennis Cordrey Bonnie Wootten |
| Planning and Zoning | (302) 855-7878 | (302) 854-5079 | Lawrence Lank |
| Press Office/ Public Information |
(302) 854-5000 | (302) 855-7749 | Chip Guy |
| Public Works | (302) 855-7703 | (302) 854-5396 | Michael Brady |
| Purchasing | (302) 854-5382 | (302) 855-7710 | Frank Shade |
| Recorder of Deeds | (302) 855-7785 | (302) 855-7787 | John Brady |
| Register of Wills | (302) 855-7875 | (302) 853-5871 | Gregory Fuller Sr. |
| Sheriff | (302) 855-7830 | (302) 855-7832 | Eric D. Swanson |
| Technical Engineering | (302) 855-7718 | (302) 855-7799 | Steven Hudson |
| Treasury Division | (302) 855-7760 | (302) 854-5078 | Amanda M. Bennett |
| Utility Billing | (302) 855-7871 | (302) 854-5381 | Patricia Faucett |
| Utility Engineering | (302) 855-7717 | (302) 854-5391 | Brad Hawkes Keith Bryan |
| Utility Permits | (302) 855-7719 | (302) 853-5881 | Gary Tonge |
| Utility Planning | (302) 855-1299 | (302) 855-7731 | John Ashman |