Backflow Testing in Illinois
Backflow Testing across Illinois: the 750 ZIP codes and 525 cities we route calls in, and who licenses plumbers in the state.
Free to homeowners in Illinois — the contractor pays us for the introduction, you never do.
Who has to test
Our backflow testing coverage in Illinois runs to 750 ZIP codes in 525 cities. In a state that mixes large systems with small ones, a testing duty that is routine on one side of a county line can be unknown on the other, and the deadline a premises is held to is whichever its own water supplier sets.
Source: coverage area as published by our call partner; place and county names from the US Census Bureau.
We route backflow testing calls in 750 ZIP codes across 525 Illinois cities, in 51 counties.
What this site is
CrossConnect is a referral service, not a contractor. We connect property owners and managers with independent contractors. Backflow assembly testing is normally restricted to testers holding a specific certification and using calibrated equipment, and the report usually has to reach your water purveyor — ask to see the certification and ask who files the report. We carry out no testing, we certify nobody, we do not set prices, and we never charge callers anything. Nothing here selects a device for any installation or states that any assembly is passing.Checking a credential in Illinois
Illinois licenses are issued by the Illinois Department of Public Health, Plumbing Program, which publishes a public search you can use before work begins.
18 of the 51 Illinois counties we cover, from the top of the alphabet
- Alexander County 6 ZIP codes
Cairo, McClure, Miller City, Olive Branch, Tamms, Thebes - Boone County 5 ZIP codes
Belvidere, Caledonia, Capron, Garden Prairie, Poplar Grove - Bureau County 8 ZIP codes
Bureau, Cherry, Dalzell, Depue, Ladd, Princeton, Spring Valley, Walnut - Carroll County 1 ZIP code
Lanark - Champaign County 33 ZIP codes
Champaign, Urbana, Bondville, Broadlands, Dewey, Fisher, Foosland, Gifford, Homer, Ivesdale, Longview, Ludlow, Mahomet, Ogden and 12 more - Coles County 6 ZIP codes
Ashmore, Charleston, Humboldt, Lerna, Mattoon, Oakland - Cook County 215 ZIP codes
Chicago, Palatine, Schaumburg, Evanston, Des Plaines, Oak Park, Arlington Heights, Hoffman Estates, Melrose Park, Chicago Heights, Elk Grove Village, Glenview, Northbrook, Oak Lawn and 80 more - De Witt County 7 ZIP codes
Clinton, DeWitt, Farmer City, Lane, Wapella, Waynesville, Weldon - DeKalb County 1 ZIP code
Waterman - Dekalb County 10 ZIP codes
Cortland, DeKalb, Genoa, Hinckley, Kingston, Kirkland, Malta, Sandwich, Somonauk, Sycamore - Douglas County 7 ZIP codes
Arcola, Arthur, Camargo, Hindsboro, Murdock, Tuscola, Villa Grove - DuPage County 2 ZIP codes
Eola, Wayne - Dupage County 57 ZIP codes
Aurora, Carol Stream, Naperville, Bensenville, Bloomingdale, Downers Grove, Glen Ellyn, Hinsdale, West Chicago, Wheaton, Wood Dale, Addison, Bartlett, Clarendon Hills and 15 more - Ford County 7 ZIP codes
Elliott, Gibson City, Melvin, Paxton, Piper City, Roberts, Sibley - Grundy County 8 ZIP codes
Braceville, Coal City, Gardner, Mazon, Minooka, Morris, South Wilmington, Verona - Iroquois County 5 ZIP codes
Buckley, Chebanse, Loda, Sheldon, Thawville - Jackson County 15 ZIP codes
Carbondale, Ava, Campbell Hill, De Soto, Dowell, Elkville, Gorham, Grand Tower, Jacob, Makanda, Murphysboro, Pomona, Vergennes - Kane County 23 ZIP codes
Elgin, Saint Charles, Batavia, Big Rock, Burlington, Carpentersville, Dundee, Elburn, Geneva, Gilberts, Hampshire, Kaneville, Maple Park, Mooseheart and 4 more
33 more Illinois counties are inside the coverage area and are not listed here. If your ZIP code is in Illinois, the call reaches a contractor.
What that coverage looks like
The 51 counties in our Illinois footprint are served by many separate water suppliers, and each one decides which premises must test and how often. Cook County, with 215 covered ZIP codes, is the largest single block of them; Chicago alone holds 85.
How a backflow testing job goes
A backflow test is a scheduled job that ends in a document. The assembly is isolated, the differential across it is measured, the result is written down, and the report goes to whoever requires it. A failed test means a repair or a rebuild and then a re-test; it does not mean the premises closes that day.
What the call asks about backflow testing
- What kind of premises it is and what is connected to the supply — irrigation, a boiler, a fire line, a commercial kitchen.
- Who is asking for the test: a water supplier, a health department, or a landlord.
- Whether there is an existing assembly with a serial number on it, and when it was last tested.
Every Illinois city we route in
188 cities, ordered by the share of buildings with twenty or more units. Containment assemblies are required building by building, and that is where the buildings are. Each page carries that city’s own numbers and the ZIP codes we route there.
- Lincolnshire 32%
- Evanston 30%
- Lisle 27%
- Chicago 27%
- Forest Park 26%
- Lombard 25%
- Oak Park 25%
- Oak Brook 23%
- Wheeling 22%
- Prospect Heights 22%
- Niles 22%
- Richton Park 22%
- Bensenville 21%
- Arlington Heights 21%
- Champaign 21%
- Itasca 20%
- Lincolnwood 19%
- Urbana 19%
- Northbrook 19%
- Skokie 19%
- Mount Prospect 18%
- Des Plaines 18%
- Rolling Meadows 18%
- Glenview 17%
- Schaumburg 17%
- Savoy 17%
- Willowbrook 17%
- Vernon Hills 16%
- Harwood Heights 16%
- Downers Grove 16%
- Elmhurst 16%
- Elk Grove Village 16%
- Morton Grove 15%
- Villa Park 15%
- Justice 14%
- Buffalo Grove 14%
- Westmont 14%
- Carbondale 13%
- Elmwood Park 13%
- Glen Ellyn 13%
- Normal 13%
- Wilmette 13%
- Bloomingdale 13%
- DeKalb 13%
- La Grange Park 13%
- River Forest 13%
- Hillside 12%
- Palos Park 12%
- La Grange 12%
- Waukegan 12%
- Palatine 12%
- Highland Park 12%
- Wheaton 11%
- Lake Forest 11%
- North Chicago 11%
- Gurnee 11%
- Carol Stream 10%
- River Grove 10%
- Crest Hill 10%
- Park Ridge 10%
- Deerfield 10%
- Melrose Park 10%
- Charleston 10%
- Lake Bluff 9%
- Clarendon Hills 9%
- Batavia 9%
- Wood Dale 9%
- Calumet City 9%
- Darien 9%
- Dundee 9%
- Harvey 9%
- Hoffman Estates 8%
- Woodridge 8%
- Rock Island 8%
- Glenwood 8%
- Kankakee 8%
- Libertyville 8%
- Naperville 8%
- Decatur 8%
- Mundelein 7%
- North Aurora 7%
- Bloomington 7%
- Barrington 7%
- Schiller Park 7%
- Chicago Ridge 7%
- Moline 7%
- Aurora 7%
- Park Forest 7%
- South Elgin 7%
- Addison 7%
- Rockford 7%
- Joliet 6%
- Oak Lawn 6%
- Lansing 6%
- Mattoon 6%
- Homewood 6%
- Roselle 6%
- Bridgeview 6%
- Danville 6%
- West Chicago 6%
- Springfield 6%
- Hazel Crest 6%
- Flossmoor 6%
- Hinsdale 6%
- Freeport 6%
- O'Fallon 6%
- Hickory Hills 6%
- Bolingbrook 6%
- Steger 6%
- Pontiac 6%
- Geneva 5%
- Glendale Heights 5%
- Bartlett 5%
- Sterling 5%
- Crestwood 5%
- Blue Island 5%
- Saint Charles 5%
- Lincoln 5%
- Fox Lake 5%
- Grayslake 5%
- Loves Park 5%
- Ingleside 5%
- Murphysboro 5%
- Lyons 5%
- Streator 5%
- Winnetka 5%
- Midlothian 4%
- Rochelle 4%
- Woodstock 4%
- Zion 4%
- Lake Zurich 4%
- Elgin 4%
- Fairview Heights 4%
- Pekin 4%
- Crete 4%
- Dixon 4%
- Riverdale 4%
- Alsip 4%
- Matteson 4%
- Lemont 4%
- Romeoville 4%
- Dolton 4%
- Chicago Heights 4%
- Maywood 4%
- Huntley 4%
- Rockton 4%
- Berwyn 4%
- Monticello 4%
- Wauconda 4%
- Summit Argo 4%
- Orland Park 3%
- Franklin Park 3%
- Ottawa 3%
- Oregon 3%
- Hanover Park 3%
- Montgomery 3%
- Country Club Hills 3%
- Algonquin 3%
- Oak Forest 3%
- Morris 3%
- Collinsville 3%
- Riverside 3%
- Mahomet 3%
- Sugar Grove 3%
- Shorewood 3%
- Round Lake 3%
- Peru 3%
- Tinley Park 3%
- Mendota 3%
- Lake Villa 3%
- Yorkville 3%
- Sandwich 3%
- Princeton 3%
- Minooka 3%
- Belvidere 3%
- La Salle 3%
- Homer Glen 3%
- McHenry 2%
- Rantoul 2%
- Lake in the Hills 2%
- Elburn 2%
- Oswego 2%
- Worth 2%
- Winfield 2%
- Belleville 2%
- Antioch 2%
- Sycamore 2%
- Palos Hills 2%
Before you call
A test is a scheduled job with a report at the end of it, not a repair. What the report has to show, and who it goes to, are on the pages above.
