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DR. MARK JOSEPH FESLER MD
NPI 1235204066
Internal Medicine - Hematology & Oncology in Saint Louis, MO

Active since November 21, 2006PECOS EnrolledAccepts Medicare Assignment
3655 VISTA AVE, SAINT LOUIS, MO 63110(314) 977-4340(314) 773-1167 Get Directions Write a Review

NPPES record last updated: March 29, 2021. Verified against the NPPES registry weekly; last sync: August 02, 2026.

Record update history: Mar 29, 2021, Jan 13, 2021, Dec 8, 2020 and 1 more (4 updates tracked since 2020).

About Dr. Mark Joseph Fesler Md NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. MARK JOSEPH FESLER MD (NPI 1235204066) is an individual hematology & oncology provider in Saint Louis, Missouri, licensed in Missouri (2008029015) and active in the NPI registry since November 2006. He is enrolled in Medicare PECOS, is affiliated with St Lukes Hospital, and is a graduate of Saint Louis University School Of Medicine (2003).

NPPES Registry Identity

NPI1235204066
Entity TypeIndividualMale
Primary Taxonomy207RH0003X
Provider Legal NameDR. MARK JOSEPH FESLERCredential: MD
Location Address3655 VISTA AVESaint Louis, MO 63110-2539
Mailing Address3655 Vista AveSaint Louis, MO 63110-2539 · (314) 977-4340 · Fax (314) 776-2287
Phone(314) 977-4340
Fax(314) 773-1167
Sole ProprietorNo
Medical School CMSSaint Louis University School Of MedicineGraduated 2003
Enumeration DateNovember 21, 2006
Last NPPES UpdateMarch 29, 20214 updates tracked since enumeration
NPPES CertifiedMarch 29, 2021
✔ NPI 1235204066 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal Medicine · Hematology & OncologyAllopathic & Osteopathic Physicians
Taxonomy Code207RH0003X
License✔ Licensed in MO · 2008029015
Definition
An internist doctor of osteopathy that specializes in the treatment of the combination of hematology and oncology disorders. A doctor of osteopathy that is board eligible/certified by the American Osteopathic Board of Internal Medicine WAS able to obtain a Certificate of Special Qualifications in the field of Hematology and Oncology. The Certificate is NO longer offered.
Also ListedInternal MedicineTaxonomy 207R00000X · License 43133 (CO)
3655 VISTA AVE, Saint Louis, MO 63110
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Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Ambetter from Arkansas Health & Wellness, Ambetter from Home State Health, Ambetter from Sunflower Health Plan and more.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Dr. Mark Joseph Fesler Md is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID3375645880
PECOS Enrollment IDI20100812000917
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Areas of Expertise CMS Part B claims 5

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more 99215
This service involves a follow-up appointment for existing patients, lasting between 40 to 54 minutes. During this time, your healthcare provider will assess your current health status, discuss any changes or concerns, review your treatment plan, and answer any questions you may have.
864 services201 patients
Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 99233
Follow-up hospital inpatient care per day typically involves a 35-minute check-up by your healthcare provider. This service includes monitoring your health progress, adjusting your treatment plan if needed, and answering any questions you may have about your condition or care.
421 services70 patients
Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 99223
Initial hospital inpatient care per day, typically 70 minutes, refers to the daily medical service provided to patients admitted to the hospital. This includes a comprehensive evaluation, diagnosis, treatment plan, and monitoring of your health condition. It ensures your well-being during your hospital stay.
124 services77 patients
New patient office or other outpatient visit with a high level of medical decision making, if using time, 60 minutes or more 99205
This is a first-time patient visit where a healthcare professional spends 60-74 minutes with you. It involves a comprehensive evaluation, including your medical history and current health condition. They'll also advise on preventive health measures and formulate a treatment plan if needed.
28 services28 patients
Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214
This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.
15 services15 patients

Hospital Affiliations CMS Care Compare

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

St Lukes Hospital

Acute Care Hospitals · Chesterfield, MO
4/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number260179
Location232 S Woods Mill RdChesterfield, MO 63017 · St. Louis County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 63110 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$169.38 typical visit price
range $55.65 – $169.38
Typical copayment $42.34 (range $13.91 – $42.34)
Most-billed visit code 99205
Established Patient
$98.37 typical visit price
range $17.76 – $137.92
Typical copayment $24.59 (range $4.44 – $34.48)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

EDDY C HSUEH MD
Surgery
3655 VISTA AVE
SAINT LOUIS, MO 63110
St. Louis City (314) 977-4440
ALEXANDRA MAYBERRY
Nurse Practitioner (Family)
3655 VISTA AVE
SAINT LOUIS, MO 63110
St. Louis City (314) 577-6056
TONYA ELAINE BUCHANAN ANP-BC
Nurse Practitioner (Adult Health)
3655 VISTA AVE, CENTER FOR BLOOD AND MARROW OUTPATIENT TRANSPLANTATION
SAINT LOUIS, MO 63110
St. Louis City (314) 577-8000
STEVEN M PINCUS MD
Internal Medicine (Hematology & Oncology)
3655 VISTA AVE
SAINT LOUIS, MO 63110
St. Louis City (314) 577-6057
NADA AL MASALMEH M.D.
Internal Medicine (Hematology & Oncology)
3655 VISTA AVE
SAINT LOUIS, MO 63110
St. Louis City (313) 858-4089
DR. CARRIE LUU MD
Surgery
3655 VISTA AVE, SURGERY, 1ST FLOOR
ST LOUIS, MO 63110
St. Louis City (314) 977-4440
DR. SUAIMAN SYED SHOAB M.D.
Surgery (Vascular Surgery)
3655 VISTA AVE
SAINT LOUIS, MO 63110
St. Louis City (314) 577-6027
DR. BASSEL JALLAD MBBS
Internal Medicine (Hematology & Oncology)
3655 VISTA AVE, WEST PAVILION
SAINT LOUIS, MO 63110
St. Louis City (314) 268-7109

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Mark Fesler's NPI number?

The NPI number for Mark Fesler is 1235204066. It was assigned to this individual provider in the NPPES registry on November 21, 2006.

Where is Mark Fesler located?

Mark Fesler practices at 3655 Vista Ave, Saint Louis, MO 63110. The listed phone number is (314) 977-4340.

What is Mark Fesler's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Hematology & Oncology, with taxonomy code 207RH0003X.

Is Mark Fesler enrolled in Medicare?

Yes. Mark Fesler is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

What insurance does Mark Fesler accept?

Health plans from Ambetter Health, Ambetter Health of Delaware, Ambetter from Arkansas Health & Wellness, Ambetter from Home State Health and Ambetter from Sunflower Health Plan and 3 other insurers list Mark Fesler as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

Is Mark Fesler affiliated with any hospitals?

According to CMS data, Mark Fesler is affiliated with St Lukes Hospital.

When was this NPI record last updated?

The NPPES record for Mark Fesler was last updated on March 29, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 5 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.