Mercy Laboratory Services - O'Fallon

Imaging, Labs or Tests
300 Winding Woods Drive
O Fallon, MO 63366

Phone: (636) 379-4301
Fax: (636) 379-4302
Monday-Friday: 7 a.m. - 5 p.m.
Services are provided by Mercy Hospital St. Louis Learn more »

We offer a full range of lab testing services. Test results are immediately transmitted to your physician’s office. Patients may also have specimens collected and tested here and the results sent to a specialist in another city. In addition to routine lab tests most often requested by your physician, we provide health screens to promote wellness and reduce health risks in our community.

Holiday Hours

Thanksgiving Eve (11/27/19): 7 a.m. - 3:30 p.m.
Thanksgiving Day (11/28/19): Closed
Day after Thanksgiving (11/29/19): Normal Business Hours

Christmas Eve (12/24/19): 7 a.m. - 3:30 p.m.
Christmas Day (12/25/19): Closed
Day after Christmas (12/26/19): Closed

New Year's Eve (12/31/19): 7 a.m. - 3:30 p.m.
New Year's Day (1/1/20): Closed
Day after New Year's Day (1/2/20): Normal Business Hours