William C. Bayer, MD

William C. Bayer, MD

4.9 
1425 ratings  Read Reviews
Northwestern Medicine logoNorthwestern Medicine Regional Medical Group

Primary Specialty

Endocrinology

Is your insurance accepted? Select plan

CALL

Education

Medical Education:
MD, Loyola University Stritch School of Medicine - 1986
Residency:
Loyola University Medical Center - 1989
Fellowships:
Loyola University Medical Center - 1991

Board Certifications

  • American Board of Internal Medicine - Endocrinology, Diabetes & Metabolism (Certified)
  • American Board of Internal Medicine - Internal Medicine (Certified)

Practice Groups and Affiliations

Medical Group:
Northwestern Medicine Regional Medical Group
Alignment Category:
Northwestern Medicine Physician Network
On Medical Staff At:
Central DuPage Hospital

Ratings and Reviews

At Northwestern Medicine, our patient’s feedback is important to us. While different care providers have their own unique strengths, we strive to be as transparent as possible with our quality of care.

Read Ratings FAQs

Overall Rating

4.9
4.9 

1425 Ratings

Sort By Newest

Reviews from Patients

100 Most Recent Reviews

Reviews from Patients

Sort By Newest
100 Most Recent Reviews

April 16, 2024

5.0

Dr Bayer is the best Endocrinologist I've found. Friendly and willing to answer all questions.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

April 15, 2024

5.0

He truly cares about my health

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

April 15, 2024

5.0

Dr.Bayer is very caring and knowledgeable.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

April 11, 2024

5.0

Great Doctor

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

April 10, 2024

5.0

Competent, supportive, trustworthy. He is the best endocrinologist I had so far.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

April 05, 2024

5.0

Keeps it real

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

April 04, 2024

5.0

Dr Bayer is very knowledgeble and also looks at all of my recent medical tests to give me an opinion. I didn't know that my glucose was too high, yet he alerted me and ordered more testing. He's too busy to fit me for another appt to deal with my possible diabetes, so will hope me PCP can and will handle it.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

April 03, 2024

5.0

Everything is good for me. Thx

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

March 27, 2024

5.0

Listed above.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

March 26, 2024

5.0

Professional, does not rush you, answers questions and gives great care.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

March 25, 2024

5.0

Great and caring doctor, very professional

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

March 25, 2024

5.0

Professional and knowledgeable

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

March 16, 2024

5.0

Dr Bayer is excellent. Very thorough and takes time to explain and answer questions took time to fix all the paperwork problems I was having. I have been with him for 35 yrs. Hoping for lots more

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

March 13, 2024

5.0

Dr Bayer is a professional with great approach to helping patients understand the full scope of their medical challenges. He was kind, patient, thorough, and attentive. I did not feel rushed. He offered details that I asked for and provided referral for additional care as needed.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

March 12, 2024

5.0

Dr Bayer is approachable and professional and kind

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

March 11, 2024

5.0

I find him knowledgeable and have confidence in his diagnosis and treatment.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

March 05, 2024

5.0

He is a good listener, he is kind. He is a good and intelligent doctor.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

March 04, 2024

5.0

Very kind and caring doctor

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 28, 2024

5.0

Dr. Bayer is knowledgeable, trusted and experienced. He is also kind and encouraging.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 27, 2024

5.0

Friendly and open to listen.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 26, 2024

5.0

Excellent care. Knowledge. Informs patient for all options. Caring. Friendly. Compassionate. Good humor.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 22, 2024

5.0

On time and very professional.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 21, 2024

5.0

Dr. Bayer is fabulous and he listens. He is empathetic and is caring. Dr. Bayer is highly educated and is current with clinical studies and data.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 20, 2024

5.0

The best

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 19, 2024

5.0

Dr Bayer is Professional and attentive

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 16, 2024

5.0

Great doctor/care provider

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 14, 2024

5.0

Outstanding doctor

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 14, 2024

5.0

He was pleasant, good bedside manner, and knowledgeable.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 14, 2024

5.0

He's very professional and understanding

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 13, 2024

5.0

Dr. Bayer continues to offer usable suggestions and helpful advice. He became aware of additional medical issues with me and tried to offer some positive advice.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 13, 2024

5.0

As I mentioned already above, Dr William Bayer is an outstanding Endocrinologist, who has managed to get my thyroid condition under perfect control. I would highly recommend Dr. Bayer to anyone.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 12, 2024

5.0

Dr. Bayer is the best person I ever had for handling my health problem.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 12, 2024

5.0

Dr. Bayer always listens to my concerns and treats me with respect and caring.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 12, 2024

5.0

Always listens to your concerns, and answers all your questions.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

February 07, 2024

5.0

Truly listens

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

January 29, 2024

5.0

Excellent listener and years experience is outstanding. And he is a genuine person.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

January 27, 2024

5.0

Been with Dr Bayer for years. He knows my condition and has developed a level of high trust with me.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

January 26, 2024

5.0

He goes above and beyond to make sure you are well taken care of

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

January 26, 2024

5.0

Very good doctor

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

January 24, 2024

5.0

doctor explain well and show concern for my health

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

January 24, 2024

5.0

Dr. Bayer is very down to earth and very easy to talk to about absolutely anything.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

January 22, 2024

5.0

Good doctor and personable

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

January 22, 2024

5.0

He is very thorough and personable. He listens

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

January 21, 2024

5.0

thorough, personable, love his clothing choices( that's a bonus. wouldn't choose a physician on that alone). a very interesting man, and a great doctor.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

January 19, 2024

5.0

He is very caring and makes me feel like he really cares

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

January 16, 2024

5.0

Destination information on health concern. Advised why there is no need for addtional changes with medication.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

January 10, 2024

5.0

Dr Bayer is GREAT!! Very knowledgeable and patient! Answered all my questions.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

January 10, 2024

5.0

Awesome doctor

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

January 08, 2024

5.0

Very through.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

January 02, 2024

5.0

He is a very good communicator.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

December 27, 2023

5.0

Great Doctor. He listens and gets to the point. He has definitely help me over the years to get my numbers in line.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

December 27, 2023

5.0

He goes through your chart and insures every lab is up to date and shares all his concerns and/or the patients.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

December 20, 2023

5.0

He is the best of the best. Focused, comprehensive, compassionate, all the elements you want in a Doctor. A superb professional for many years. Bravo!

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

December 19, 2023

5.0

Dr. Bayer is absolutely amazing and will take such good care of you.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

December 14, 2023

5.0

Excellent attention to my symtons and medical concerns.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

December 14, 2023

5.0

Been a patient for over 20 years and had nothing but outstanding attention and care

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

December 13, 2023

5.0

Dr. very friendly & kind

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

December 11, 2023

5.0

Great doctor. Great bedside manner

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

December 07, 2023

5.0

Doesn’t prescribe all kinds of meds. Right to the point.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

December 06, 2023

5.0

Expert,professional,conversational.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

December 06, 2023

5.0

Found him experienced and informative.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

December 06, 2023

5.0

I feel he is thorough and discusses all levels that blood work indicates. He is friendly and personable. I see him on a yearly + basis but he remembers me.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

December 05, 2023

5.0

Listens well, answers all questions

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

December 04, 2023

5.0

As stated, I like Dr Bayer. I feel comfortable with him and I appreciate his allowing me to explain things and he always answers my questions.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

December 04, 2023

5.0

very understanding

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

December 04, 2023

5.0

He’s an incredible doctor and compassionate person. I know I’m in good hands.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

November 30, 2023

5.0

Dr Bayer is an excellent doctor and very through

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

November 28, 2023

5.0

He is very caring and explains things welll.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

November 27, 2023

5.0

He listens to your concerns and don't rush you out

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

November 27, 2023

5.0

I love his personality! He always puts me at ease because he is very knowledgeable, professional, caring and friendly.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

November 25, 2023

5.0

Excellent attention

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

November 20, 2023

5.0

He knows his stuff and answered all my questions

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

November 20, 2023

5.0

He is friendly, skilled and professional.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

November 19, 2023

5.0

Caring and professional all with amazing bedside manner

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

November 15, 2023

5.0

He’s BRILLIANT! He’s professional; knowledgeable; trustworthy; highly-intelligent; a good listener to patient’s questions; courteous; and an enjoyable bedside manner.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

November 15, 2023

5.0

I have been a patient for his for a very long time. I also have referred my daughter who has been seeing for many years and my sister. We are all extremely happy with his care

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

November 14, 2023

5.0

He's a new doctor for me and I like him

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

November 13, 2023

5.0

I respect his knowledge and love his attitude and ability to communicate. I trust him.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

November 13, 2023

5.0

Dr. Bayer was welcoming and took time to answer any questions I had.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

November 08, 2023

5.0

I value his decisions.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

November 08, 2023

5.0

Have been a patient of Dr. Bayer’s since 1999 and can’t imagine trusting anyone else with my diabetes care.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

November 04, 2023

5.0

Personal, thorough, explains things well, & ask questions.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 30, 2023

5.0

He is very understanding, knowledgeable & great bedside manner!!

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 28, 2023

5.0

Exceptional care.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 27, 2023

5.0

Attention to detail and a wide scientific knowledge of the endocrine system.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 24, 2023

5.0

Dr Bayer clearly explains all tests and procedure results.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 18, 2023

5.0

The Chi in Indian caring attitude of the doctor

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 18, 2023

5.0

Kind and caring. One of the truly finest doctors at Northwestern Medicine.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 17, 2023

5.0

Dr. Bayer actually listens to what I say and responds accordingly.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 11, 2023

5.0

Very nice staff

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 10, 2023

5.0

I have been seeing him for years and I and very pleased with the care he has given me

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 10, 2023

4.0

They just need to run on time. I know things happpen but if your appointment is at a certain time you should be seeing the physician within 15 mins of the start of the appointment

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 10, 2023

5.0

I would highly recommend Dr. Bayer for care to others based on my own experience with him. Dr. Bayer actually cares about his patients and that makes all the difference.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 09, 2023

5.0

Knowledgeable, supportive, trustworthy

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 09, 2023

5.0

He is wonderful, knowledgable and caring.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 09, 2023

5.0

He’s honest, caring and really listens to my needs.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 09, 2023

5.0

He’s very respectful of me and always happy to see me.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 09, 2023

5.0

professional and convenient.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 09, 2023

5.0

While I would want to recommend Dr Bayer as he has kept my diabetes and other health issues under control. However I hesitate to recommend him because it is already difficult to get an appt with him. He is too popular!

Was this helpful? Yes (0) No (0)

Thanks for your feedback!

October 07, 2023

5.0

Have had him for many years.

Was this helpful? Yes (0) No (0)

Thanks for your feedback!
View more reviews

Disclosures

William C. Bayer, MD reported no external professional relationships for calendar year 2023.

External Professional Relationships

Pharmaceutical, device, and biotechnology companies frequently collaborate with basic scientists and physicians within an academic medical center to help advance science and improve patient care. These relationships are important in achieving scientific breakthroughs and in establishing the effectiveness and safety of promising new therapies. In order to assure objectivity in clinical research and patient care, the Northwestern University Feinberg School of Medicine (Feinberg), Northwestern Memorial HealthCare, Children's Hospital of Chicago Medical Center, and the Shirley Ryan AbilityLab have adopted integrity policies that require research and clinical faculty (in full-time, part-time, and unpaid/voluntary categories) to report compensated and uncompensated external industry relationships. Patients are encouraged to discuss these disclosures with their physician as well as to inquire as to how these relationships are overseen by Feinberg. To learn more about our Disclosure and Professional Integrity Policy, and the conflict of interest policies of our joint affiliate survey partners, please go to our Office for Regulatory Affairs Policies page.

View More Disclosures