General customer service for Quest Diagnostics can be contacted by phone by calling 866-MYQUEST (866-697-8378), according to the company's website. However, Quest Diagnostics has different customer service numbers for different relationships, services and divisions.
When calling the general customer service line, an automated system provides prompts to reach the proper department, such as selecting option 1 for clients or option 2 for patients. The company's website also provides phone numbers for other departments. The customer service number for patients undergoing clinical trials is (800) 877-7004, and the customer service number for employer relations is (800) 877-7484.
Patients who have questions or comments about billing, locations, appointments or patient service centers can also contact customer service via email on the company's website. Specific links are provided for each category. Additional customer service options can be found on QuestDiagnostics.com by clicking on the "Contact Us" tab and then navigating to the "Customer Service" page.
Quest Diagnostics provides diagnostic testing products and services that help doctors and patients make better health care decisions. Services range from routine blood tests like total cholesterol or white blood cell count to more complex genetic and molecular testing. The company also provides clinical trials and laboratory services for pharmaceutical, biotechnology and medical device manufacturing companies.