DR. STEPHEN T ANG MD
NPI 1346251071
Internal Medicine - Gastroenterology in Centralia, IL

Q: What is Stephen Ang's NPI number?

The NPI number for Stephen Ang is 1346251071. It was assigned to this individual provider in the NPPES registry on August 10, 2006.

Q: What is Stephen Ang's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Gastroenterology, with taxonomy code 207RG0100X.

Q: When was this NPI record last updated?

The NPPES record for Stephen Ang was last updated on July 8, 2007. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 19 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.

Active since August 10, 2006PECOS EnrolledAccepts Medicare Assignment

75/100

CMS Quality Rating

1054 M L KING DR, SUITE 120, CENTRALIA, IL 62801(618) 532-1688(618) 532-1689 Get Directions Write a Review

NPPES record last updated: July 8, 2007. Verified against the NPPES registry weekly; last sync: October 25, 2026.

On this page

About Dr. Stephen T Ang Md NPPES

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

DR. STEPHEN T ANG MD (NPI 1346251071) is an individual gastroenterology provider in Centralia, Illinois and active in the NPI registry since August 2006. He is enrolled in Medicare PECOS, is affiliated with Ssm Health St Mary's Hospital -centralia, and is a graduate of University Of California, Geffen School Of Medicine (1991).

NPPES Registry Identity

NPI1346251071

Entity TypeIndividualMale

Primary Taxonomy207RG0100X

Provider Legal NameDR. STEPHEN T ANGCredential: MD

Location Address1054 M L KING DR, SUITE 120Centralia, IL 62801-3000

Mailing Address1054 M L King Dr, Suite 120Centralia, IL 62801-3000 · (618) 532-1688 · Fax (618) 532-1689

Phone(618) 532-1688

Fax(618) 532-1689

Sole ProprietorNo

Medical School CMSUniversity Of California, Geffen School Of MedicineGraduated 1991

Enumeration DateAugust 10, 2006

Last NPPES UpdateJuly 8, 2007

✔ NPI 1346251071 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · GastroenterologyAllopathic & Osteopathic Physicians

Taxonomy Code207RG0100X

Definition

An internist who specializes in diagnosis and treatment of diseases of the digestive organs including the stomach, bowels, liver and gallbladder. This specialist treats conditions such as abdominal pain, ulcers, diarrhea, cancer and jaundice and performs complex diagnostic and therapeutic procedures using endoscopes to visualize internal organs.

1054 M L KING DR, Centralia, IL 62801

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Other Identifiers 3

Medicare UPING25820

Other06107347IL · Blue Cross Blue Shield

Medicare ID-Type Unspecified466860IL

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Ambetter Health, Ambetter Health of Delaware.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Dr. Stephen T Ang 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 ID1254370448

PECOS Enrollment IDI20050427000717

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.

Medicare Billing Reassignments

Medicare enrollment records show Stephen Ang reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

St. Mary's Hospital, Centralia, Illinois

0.9 mi

Anesthesiology

400 N PLEASANT AVE
Centralia, IL 62801

Reassigned Medicare billing, Illinois enrollment
Medicare enrollment name: St Marys Hospital Centralia Illinois
392 clinicians in this Medicare group

NPI 1477097871 (618) 436-6056

Stephen T Ang MD Sc

1.0 mi

Gastroenterology

1054 MARTIN LUTHER KING DR, STE 120
Centralia, IL 62801

Reassigned Medicare billing, Illinois enrollment

NPI 1427331891 (618) 532-1688

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Areas of Expertise CMS Part B claims 15

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 low level od decision making, if using time, 20 minutes or more 99213

This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.

710 services416 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.

248 services212 patients

New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more 99204

This is a first-time office or outpatient visit lasting between 45-59 minutes. The healthcare provider evaluates your health, discusses your medical history, and may suggest further tests or treatments. It's an opportunity to ask questions and understand your health better.

181 services181 patients

Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 43239

This procedure involves using a thin, flexible tube with a light and camera, known as an endoscope, to examine the esophagus, stomach, and upper part of the small intestine. Small tissue samples are taken for further examination to help diagnose various conditions.

109 services108 patients

New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more 99203

This service involves an initial office or outpatient visit for a new patient. The healthcare professional will spend 30-44 minutes understanding your health history, current issues, and discussing possible treatment plans. It's a comprehensive evaluation to start your healthcare journey.

86 services86 patients

Colorectal cancer screening; colonoscopy on individual at high risk G0105

Colorectal cancer screening, specifically a colonoscopy, is a preventive measure for those at high risk. A thin, flexible tube with a camera inspects the colon to spot any abnormal growths. This test helps detect potential issues early, enhancing the effectiveness of treatment.

84 services84 patients

Removal of polyps or growths of large bowel using an endoscope with mechanical snare 45385

This procedure involves using a thin, flexible tube called an endoscope to examine the large bowel. If any abnormal growths or polyps are found, a tool called a mechanical snare is used to remove them. This is a common method to prevent potential health issues.

77 services76 patients

Diagnostic exam of esophagus, stomach, and/or upper small bowel using a flexible endoscope 43235

This procedure, known as an upper endoscopy, involves inserting a thin, flexible tube with a camera down the throat to examine the esophagus, stomach, and upper small bowel. It helps diagnose conditions like ulcers or inflammation.

47 services47 patients

Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 99222

Initial hospital inpatient care is a service where a healthcare provider spends about 50 minutes per day overseeing your care while you're admitted in the hospital. This includes reviewing your health status, planning your treatment, and ensuring your safety and comfort.

35 services34 patients

Diagnostic exam of large bowel using a flexible endoscope 45378

This procedure, known as a colonoscopy, involves using a flexible tube with a light and camera to examine the large intestine. It helps detect any abnormalities such as polyps or inflammation. It's a standard procedure to ensure gut health.

32 services31 patients

Colorectal cancer screening; colonoscopy on individual not meeting criteria for high risk G0121

Colorectal cancer screening, such as a colonoscopy, is a preventive measure to detect early signs of cancer in the large intestine. For individuals not at high risk, it's typically recommended at age 50. A small, flexible tube with a camera is used to examine your colon. It's a safe, effective way to catch issues early.

31 services31 patients

Removal of polyps or growths of large bowel using a flexible endoscope with electrical cautery 45384

This procedure involves using a flexible tube with a camera, called an endoscope, to view the large intestine. If any abnormal growths or polyps are found, they are removed with an electrically-heated instrument. This is a common way to prevent bowel issues.

30 services30 patients

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 99232

Follow-up hospital inpatient care involves daily check-ups while you're admitted in the hospital. Typically, a healthcare provider spends about 25 minutes each day reviewing your condition, adjusting treatment if needed, and answering any questions you might have.

30 services16 patients

Subsequent hospital care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes 99231

Follow-up hospital inpatient care is a daily service where a healthcare professional checks on your health progress during your hospital stay. Each session typically lasts 15 minutes, involving updates on your condition and adjustments to your treatment plan, if necessary.

22 services19 patients

Biopsy of large bowel using a flexible endoscope 45380

A biopsy of the large bowel using a flexible endoscope is a procedure where a thin, flexible tube with a camera is inserted through the rectum to examine the bowel. If abnormal tissue is found, a small sample is taken for further examination. This helps in diagnosing conditions like inflammation, polyps, or cancer.

15 services15 patients

Hospital Affiliations CMS Care Compare 2

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

Ssm Health St Mary's Hospital -Centralia

Acute Care Hospitals · Centralia, IL

3/5 CMS rating

OwnershipVoluntary non-profit - Church

CMS Certification Number140034

Location400 North Pleasant AvenueCentralia, IL 62801 · Marion County

Emergency services

Good Samaritan Regional Hlth Center

Acute Care Hospitals · Mount Vernon, IL

2/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number140046

Location1 Good Samaritan WayMount Vernon, IL 62864 · Jefferson County

Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 62801 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

$127.46 typical visit price

range $54.80 – $168.44

Typical copayment $31.86 (range $13.70 – $42.11)

Most-billed visit code 99204

Established Patient

$97.25 typical visit price

range $17.16 – $136.56

Typical copayment $24.31 (range $4.29 – $34.14)

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.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

75/100

MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program

Individually scored

Other Providers at the Same Location NPPES 2

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

DR. SURESH KRISHNAMOORTHY M.D.

Internal Medicine (Geriatric Medicine)

1054 M L KING DR, SUITE 126
CENTRALIA, IL 62801

Marion County (618) 533-5500

SURESH KRISHNAMOORTHY MD SC

Internal Medicine (Geriatric Medicine)

1054 M L KING DR, SUITE 126
CENTRALIA, IL 62801

Marion County (618) 533-5500

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 Stephen Ang's NPI number?

The NPI number for Stephen Ang is 1346251071. It was assigned to this individual provider in the NPPES registry on August 10, 2006.

Where is Stephen Ang located?

Stephen Ang practices at 1054 M L King Dr Suite 120, Centralia, IL 62801. The listed phone number is (618) 532-1688.

What is Stephen Ang's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Gastroenterology, with taxonomy code 207RG0100X.

Is Stephen Ang enrolled in Medicare?

Yes. Stephen Ang 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.

Which organizations bill Medicare for Stephen Ang's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Stephen Ang reassigns Medicare benefits to 2 organizations: St. Mary's Hospital, Centralia, Illinois (Centralia, IL) and Stephen T Ang MD Sc (Centralia, IL). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Stephen Ang's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Stephen Ang accept?

Health plans from Ambetter Health and Ambetter Health of Delaware list Stephen Ang 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 Stephen Ang affiliated with any hospitals?

According to CMS data, Stephen Ang is affiliated with Ssm Health St Mary's Hospital -Centralia and Good Samaritan Regional Hlth Center.

When was this NPI record last updated?

The NPPES record for Stephen Ang was last updated on July 8, 2007. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 19 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.