Quest Diagnostics

Lab Testing at Mercy Hospital Washington

Hospital outpatient lab in Washington, MO 63090.

Hospital Outpatient Lab

This is a hospital outpatient lab. Most hospital outpatient labs accept walk-in third-party lab orders, but some require a physician referral or appointment. Calling ahead is recommended.

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Note: tests available at this location depend on its services. Confirm by calling before visiting.

Address

901 E 5th St 1st Floor
Washington, MO 63090
Franklin County

636-239-8000

Hours

Monday	8:00 AM – 5:00 PM
Tuesday	8:00 AM – 5:00 PM
Wednesday	8:00 AM – 5:00 PM
Thursday	8:00 AM – 5:00 PM
Friday	8:00 AM – 5:00 PM
Saturday	Closed
Sunday	Closed

Nearby alternatives

Quest Diagnostics - Mercy Patients First
901 Patients First Dr, Washington, MO 63090
0.3 mi
LabCorp Wentzville
801 Medical Dr Ste 100, Wentzville, MO 63385
19.8 mi
Quest Diagnostics - Wentzville - Employer Drug Testing Not Offered
1201 Wentzville Pkwy Ste 117, Wentzville, MO 63385
20.3 mi
Quest Diagnostics - Eureka
98 The Legends Pkwy Ste 108, Eureka, MO 63025
20.6 mi
Quest Diagnostics - O'fallon
3449 Pheasant Meadow Dr Ste 101, O Fallon, MO 63368
21.2 mi

About this location

Hospital outpatient lab. Quest Diagnostics operates one of the largest networks of clinical laboratories in the United States, offering a wide range of diagnostic tests for patients, physicians, and employers.

Listing last updated 2026-04-25.