ED
Eurofins DW and WW Central - Lima
1101 North Cole Street, Lima, OH
State-certified water testing labs in Ohio
45 state-accredited labs for drinking and well water testing in Ohio.
13 cities & counties45 certified labs
Source: Ohio EPA list of labs certified for public drinking water, list dated Oct 1, 2026. Find a Water Test is independent and not affiliated with Ohio EPA. Certification covers specific tests, so confirm the lab is certified for the ones you need: Verify a certification or call Ohio EPA lab certification at (614) 644-2752.
Major cities
Counties in Ohio A–Z
Smaller counties in Ohio
Counties with only a few listings so far, grouped by county.
Allen County 1
Columbiana County 1
LW
Leetonia WTP Laboratory
1 Saint Peter's Street, Leetonia, OH
Public water system lab. Many don't accept private well samples, so call first.
Coshocton County 1
CE
Coshocton Environmental Testing, LLC
709 Main Street, Coshocton, OH
Erie County 1
EC
Erie County Health Department Laboratory
420 Superior Street, Sandusky, OH
Public water system lab. Many don't accept private well samples, so call first.
Greene County 1
GC
Greene County Sanitary Engineering Laboratory
422 Factory Road, Beavercreek, OH
Public water system lab. Many don't accept private well samples, so call first.
Henry County 1
KW
Kleinfelder Water Technologies Laboratory
2926 U.S. Highway 6, McClure, OH
Holmes County 1
EL
Edenridge Laboratory, Ltd.
3559 U.S. Highway 62, Millersburg, OH
Jackson County 1
JC
Jackson County Water Company Laboratory
124 West Huron Street, Jackson, OH
Public water system lab. Many don't accept private well samples, so call first.
Logan County 1
LC
Logan County Health District Laboratory
310 South Main Street, Bellefontaine, OH
Public water system lab. Many don't accept private well samples, so call first.
Marion County 1
ED
Eurofins DW and WW Central - Marion
1776 Marion-Waldo Road, Marion, OH
Medina County 1
EL
Eastern Lab Services, Ltd.
1035 Medina Road, Suite 500, Medina, OH
Mercer County 1
CW
Celina Water Department Laboratory
714 South Sugar Street, Celina, OH
Public water system lab. Many don't accept private well samples, so call first.
Miami County 1
TW
Troy Water Plant Laboratory
300 E Staunton Rd., Troy, OH
Public water system lab. Many don't accept private well samples, so call first.
Morgan County 1
SW
SafeSource Water Analytics LLC
31 S. Kennebec Avenue, McConnelsville, OH
Pickaway County 1
CW
Circleville WTP Laboratory
663 Island Road, Circleville, OH
Public water system lab. Many don't accept private well samples, so call first.
Portage County 1
PC
Portage County Water Resources
8116 Infirmary Road, Ravenna, OH
Public water system lab. Many don't accept private well samples, so call first.
Seneca County 1
BE
BoJhun Environmental Services
222 S. Main Street, Fostoria, OH
Union County 1
ML
MASI Laboratory
8235 Estates Parkway, Plain City, OH
Washington County 1
ML
Microbac Laboratories, Inc. - Marietta Division
158 Starlight Drive, Marietta, OH
Williams County 1
BW
Bryan Water Plant Laboratory
841 East Edgerton Street, Bryan, OH
Public water system lab. Many don't accept private well samples, so call first.
Wood County 1
JH
Jones & Henry Laboratories
2567 Tracy Road, Northwood, OH
Mail-in labs that ship to Ohio
How mail-in testing worksNT
National Testing Laboratories (WaterCheck)
Ships nationwide
Single tests from $75; well and city packages $165 to $440
Not on Ohio's certified list. Fine for a general check; for a home sale or an official result, use a Ohio-certified lab.
TS
Tap Score by SimpleLab
Ships nationwide
Single-contaminant kits from about $145; full well and city panels about $300 to $870
Testing service: sends your sample to a partner lab.
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Just need a lab? Every certified lab is listed above with directions.