What is the largest laboratory in the United States?
Quest Diagnostics is the largest laboratory the United States in 2025.What are the largest laboratories in the United States in 2025?
Quest Diagnostics, LabCorp and Ascension Health Imaging are the largest laboratories in the United States in 2025 based on the number of locations. Quest Diagnostics has the most number of locations with 5,787 locations across 52 states and territories. LabCorp has 2,272 and Ascension Health Imaging has 345 locations in the US. These three together make 92.93% of the largest 10 laboratories in the US.
Rank | Brand | Number of Locations | States Present In | Cities Present In | Download Dataset | |
---|---|---|---|---|---|---|
#1 |
![]() |
Quest Diagnostics | 5,787 | 52 | 2,476 | |
#2 |
![]() |
LabCorp | 2,272 | 48 | 1,344 | |
#3 |
![]() |
Ascension Health Imaging | 345 | 12 | 144 | |
#4 |
![]() |
Any Lab Test Now | 238 | 32 | 207 | |
#5 |
![]() |
Ascension Health Laboratory | 197 | 12 | 106 |
Disclaimer: Brand logos are used for visual representation only and do not imply endorsement or affiliation.
Learn more about Top 5 laboratories in the United States in 2025

Quest Diagnostics
There are 5,787 Quest Diagnostics clinics in the United States as of July 28, 2025. The state and territory with the most number of Quest Diagnostics locations in the US is Texas, with 660 clinics, which is about 11% of all Quest Diagnostics clinics in the US.
Read Report Buy Dataset
LabCorp
There are 2,268 LabCorp locations in the United States as of August 04, 2025. The state and territory with the most number of LabCorp locations in the US is California, with 347 locations, which is about 15% of all LabCorp locations in the US.
Read Report Buy Dataset
Ascension Health Imaging
There are 345 Ascension Health Imaging clinics in the United States as of October 24, 2023. The state and territory with the most number of Ascension Health Imaging locations in the US is Michigan, with 101 clinics, which is about 29% of all Ascension Health Imaging clinics in the US.
Read Report Buy Dataset
Any Lab Test Now
There are 238 Any Lab Test Now locations in the United States as of May 02, 2024. The state and territory with the most number of Any Lab Test Now locations in the US is Texas, with 69 locations, which is about 29% of all Any Lab Test Now locations in the US.
Read Report Buy Dataset
Ascension Health Laboratory
There are 197 Ascension Health Laboratory locations in the United States as of September 26, 2023. The state and territory with the most number of Ascension Health Laboratory locations in the US is Michigan, with 87 locations, which is about 44% of all Ascension Health Laboratory locations in the US.
Read Report Buy DatasetNote: To ensure accurate industry categorization, we utilize NAICS codes, which classify businesses by their main economic activity. As a result, companies may appear in different industry location reports based on their primary NAICS classification. For instance, Walmart is classified as a department store under NAICS.
Download this data in any format
We provide all of our data sets as an Excel / CSV file. Please contact us if you need this POI dataset as JSON, Esri Shapefile, GeoJSON, KML (Google Earth) or any other custom format at an additional cost per format.Contact Sales