Quest Diagnostics
Quest Diagnostics provides laboratory diagnostic testing and services to patients, physicians, hospitals, health insurers, employers and government agencies.
What you need to know about Quest Diagnostics
The biggest problem customers have with Quest Diagnostics (the only problem, as far as we can tell) is overbilling. Quest customers complain about getting overcharged for their lab work. We've covered it before and we will probably cover it again. The company requested payment from the patient a year after the claim was closed.
- Quest Diagnostics’ customer service response times can vary depending on the method of contact, the volume of inquiries, and the nature of the issue.
- You can resolve a problem with Quest Diagnostics with our insider guide or through our executive contacts.
- Quest Diagnostics' customer service policies are standard. Here are our frequently asked questions about Quest Diagnostics.
How to resolve a problem with Quest Diagnostics
Try self-service first
Use our proven resolution methods, or Quest Diagnostics’s self-service links below.
Contact an executive
Start with the primary contact below, then escalate step by step if needed.
Get free advocacy help
Contact Elliott Advocacy for free mediation of unresolved complaints.
Note: If you’re having customer service trouble, please use our proven methods for fixing any consumer problem before contacting a manager.
We care about accuracy. If any of the following email addresses bounce back or the phone numbers are incorrect, please report it to us immediately through this form.
How fast does Quest Diagnostics respond?
Phone support
For further information please call (855) 392-6361 between 7:00 a.m. to 5:00 p.m. Pacific time from Monday – Friday.
Email support
No email support available. Online contact form available at questdiagnostics.com. Response time from one to three business days.
Live chat support
Quest does not currently offer live chat.
Social media
Active on Facebook and X (@QuestDx); limited support scope — directed to phone for sensitive issues.
Access Quest Diagnostic's social media accounts here.
Access Quest Diagnostic's social media accounts here.
Help center/FAQ
Available at myquest.questdiagnostics.com covers billing, results, appointments, and MyQuest
Verified contacts
Quest Diagnostics customer service executives
Maintained by Elliott Advocacy and updated regularly. Here’s how we do it →
Primary
Linda M. Taylor
Quest Experience Support Senior Manager
Primary
Maria Cecilia Gualberto
Manager Quest Experience Support
Quest Diagnostics self-service links
Log in to the MyQuest patient portal, where you can access your lab test results on any web-enabled device, schedule appointments, use the Quest AI Companion for help understanding your results, and in some cases purchase testing.
Quest Diagnostics customer service policies
Quest Diagnostics collects personal and health information from patients and website users to provide diagnostic services, process billing, and improve care. The company does not sell personal information and treat all health-related information as confidential. As a HIPAA-covered entity, they protect your "protected health information" (PHI) and may only share it for purposes such as treatment, billing, healthcare operations, or as required by law. If your data is ever used for a materially different purpose than originally collected, Quest will give you the opportunity to opt out, and sensitive data such as medical conditions or racial/ethnic origin will never be used for unrelated purposes without your explicit consent. Your data is retained only as long as necessary for legitimate business or legal purposes, and you can direct privacy-related questions or complaints to privacy@questdiagnostics.com
Quest Diagnostics loyalty program
Quest Diagnostics does not have a loyalty program.
Frequently asked questions about Quest Diagnostics
Yes, you can find the online contact form here.
Call the main customer service line at (866) 697-8378 or use the online contact form.
Monday to Friday 7 a.m. to 6 p.m.; Saturday 7:30 a.m. to 4 p.m. (all times Central). Quest Mobile is available from 7 a.m. to 5 p.m. Pacific time, Monday to Friday.
Schedule an appointment online through the Quest Diagnostics website or MyQuest app, or by calling the customer service number at (866) 697-8378. Walk-ins are also accepted at many locations, but appointments are recommended.
Use the "Find a Location" feature on the Quest Diagnostics website to search for a location by entering your city, state, or ZIP code.
Bring a valid photo ID, your insurance card, the test order from your doctor (if not sent to Quest by the doctor's office), and any other specific instructions from your healthcare provider.
Test results can be accessed online through the MyQuest portal or app. You can also request to have your results mailed to you or sent directly to your healthcare provider.
The time it takes to receive test results can vary depending on the test. Some results are available within 24 hours, while others may take several days. Check with the Quest Diagnostics representative or your healthcare provider for specific timelines.
Contact your healthcare provider for interpretation and guidance. Quest Diagnostics customer service can provide general information but cannot offer medical advice.
Pay your bill online through the Quest Diagnostics website or MyQuest portal, by phone, or by mailing a check to the address provided on your bill.
Quest Diagnostics accepts a wide range of insurance plans. Check the website for a list of accepted insurance providers or contact customer service for specific inquiries.
Log into your MyQuest account, contact customer service, or provide the updated information at the time of your appointment.
Contact Quest Diagnostics billing customer service at (866) 697-8378.
Outdated info? Report it here
Disclaimer: Contact information is believed reliable but not guaranteed. Executives change contact details frequently. If an email bounces or a number is wrong, report it immediately. Published September 15, 2020. Updated July 16, 2026.