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WILLIAM P. SULLIVAN D.O.
NPI 1902911027
Emergency Medicine in Frankfort, IL

Active since August 20, 2006PECOS EnrolledAccepts Medicare Assignment
21200 S LA GRANGE RD # 365, FRANKFORT, IL 60423(877) 778-5449(877) 778-5449 Get Directions Write a Review

NPPES record last updated: March 14, 2025. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Mar 14, 2025, Feb 18, 2016 (2 updates tracked since 2016).

About William P. Sullivan D.o. NPPES

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

WILLIAM P. SULLIVAN D.O. (NPI 1902911027) is an individual emergency medicine provider in Frankfort, Illinois, licensed in Illinois (036088666) and active in the NPI registry since August 2006. He is enrolled in Medicare PECOS, is affiliated with Osf Saint Elizabeth Mdl Ctr, and is a graduate of New York College Of Osteo Medicine Of New York Institute Of Technology (1992).

NPPES Registry Identity

NPI1902911027
Entity TypeIndividualMale
Primary Taxonomy207P00000X
Provider Legal NameWILLIAM P. SULLIVANCredential: D.O.
Location Address21200 S LA GRANGE RD # 365Frankfort, IL 60423-2003
Mailing Address21200 S La Grange Rd # 365Frankfort, IL 60423-2003 · (877) 778-5449 · Fax (877) 778-5449
Phone(877) 778-5449
Fax(877) 778-5449
Sole ProprietorYes
Medical School CMSNew York College Of Osteo Medicine Of New York Institute Of TechnologyGraduated 1992
Enumeration DateAugust 20, 2006
Last NPPES UpdateMarch 14, 20252 updates tracked since enumeration
NPPES CertifiedMarch 14, 2025
✔ NPI 1902911027 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyEmergency MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207P00000X
Licenses✔ Licensed in IL · 036088666✔ Licensed in IN · 02001489A
Definition
An emergency physician focuses on the immediate decision making and action necessary to prevent death or any further disability both in the pre-hospital setting by directing emergency medical technicians and in the emergency department. The emergency physician provides immediate recognition, evaluation, care, stabilization and disposition of a generally diversified population of adult and pediatric patients in response to acute illness and injury.
21200 S LA GRANGE RD # 365, Frankfort, IL 60423
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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

William P. Sullivan D.o. 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 ID7810885035
PECOS Enrollment IDI20040309000923
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

6

Medicare enrollment records show William Sullivan reassigns Medicare billing to 6 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

The Board Of Trustees Of The University Of Illinois
20 mi
Federally Qualified Health Center (FQHC)
8131 S MAY ST
Chicago, IL 60620
  • Reassigned Medicare billing, Illinois enrollment
  • 2,127 clinicians in this Medicare group
NPI 1952713323 (312) 996-4656
Rochelle Community Hospital Association
69 mi
Family Medicine
900 N 2ND ST STE 200
Rochelle, IL 61068
  • Reassigned Medicare billing, Illinois enrollment
  • Also billed through NPI 1821053216 (Illinois)
  • 38 clinicians in this Medicare group
NPI 1568518322 (815) 562-3784
Rockford Health Physicians
80 mi
Multi-Specialty
8201 E RIVERSIDE BLVD
Rockford, IL 61114
  • Reassigned Medicare billing, Illinois enrollment
  • 1,375 clinicians in this Medicare group
NPI 1043242886 (608) 314-2428
Epss, LLC- Metro Series
107 mi
Emergency Medicine
221 NE GLEN OAK AVE
Peoria, IL 61636
  • Reassigned Medicare billing, Illinois enrollment
  • 52 clinicians in this Medicare group
NPI 1124782305 (309) 672-5522
Osf Multi-Specialty Group
107 mi
Internal Medicine
8600 N STATE ROUTE 91
Peoria, IL 61615
  • Reassigned Medicare billing, Illinois enrollment
  • 2,944 clinicians in this Medicare group
NPI 1154908929 (309) 683-5050
Pekin Memorial Hospital
113 mi
General Acute Care Hospital
600 S 13TH ST
Pekin, IL 61554
  • Reassigned Medicare billing, Illinois enrollment
  • 42 clinicians in this Medicare group
NPI 1245227479 (309) 347-1151

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 4

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.

Emergency department visit with moderate level of medical decision making 99284
An emergency department visit for a high-severity issue means you're experiencing a serious health problem that needs immediate attention. This could be a severe injury, serious illness, or life-threatening condition. Medical professionals will provide urgent care to stabilize your condition.
172 services165 patients
Emergency department visit with high level of medical decision making 99285
An emergency department visit for severe conditions is when you urgently seek medical help due to serious health issues. These could be severe injuries, breathing problems, unbearable pain, or sudden severe illness. Doctors and nurses will provide immediate care to stabilize your condition.
112 services111 patients
Critical care, first 30-74 minutes 99291
Critical care involves immediate and constant attention by a team of specially-trained health professionals. It's for patients with life-threatening conditions, requiring first 30-74 minutes of intense monitoring and treatment.
76 services74 patients
Emergency department visit with low level of medical decision making 99283
An emergency department visit for a problem of moderate severity involves immediate medical attention for issues like minor fractures, burns, or high fever. The healthcare team will assess your condition, provide necessary treatment, and may suggest further tests or admission if required.
59 services59 patients

Hospital Affiliations CMS Care Compare 2

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

Osf Saint Elizabeth Mdl Ctr

Acute Care Hospitals · Ottawa, IL
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number140110
Location1100 E Norris DriveOttawa, IL 61350 · La Salle County
Emergency services Birthing friendly

Rochelle Community Hospital

Critical Access Hospitals · Rochelle, IL
OwnershipVoluntary non-profit - Private
CMS Certification Number141312
Location900 N 2nd StRochelle, IL 61068 · Ogle County
Emergency services

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 60423 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
$93.02 typical visit price
range $59.81 – $181.38
Typical copayment $23.25 (range $14.95 – $45.34)
Most-billed visit code 99203
Established Patient
$105.07 typical visit price
range $19.15 – $147.12
Typical copayment $26.26 (range $4.78 – $36.78)
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.

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 William Sullivan's NPI number?

The NPI number for William Sullivan is 1902911027. It was assigned to this individual provider in the NPPES registry on August 20, 2006.

Where is William Sullivan located?

William Sullivan practices at 21200 S La Grange Rd # 365, Frankfort, IL 60423. The listed phone number is (877) 778-5449.

What is William Sullivan's specialty?

The primary specialty registered for this NPI is Emergency Medicine with taxonomy code 207P00000X.

Is William Sullivan enrolled in Medicare?

Yes. William Sullivan 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 William Sullivan's services?

According to the CMS Revalidation Reassignment List (October 2026 release), William Sullivan reassigns Medicare benefits to 6 organizations: The Board Of Trustees Of The University Of Illinois (Chicago, IL), Rochelle Community Hospital Association (Rochelle, IL), Rockford Health Physicians (Rockford, IL), Epss, LLC- Metro Series (Peoria, IL), Osf Multi-Specialty Group (Peoria, IL) and 1 more organization, listed in the Medicare section above. 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 William Sullivan's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

Is William Sullivan affiliated with any hospitals?

According to CMS data, William Sullivan is affiliated with Osf Saint Elizabeth Mdl Ctr and Rochelle Community Hospital.

When was this NPI record last updated?

The NPPES record for William Sullivan was last updated on March 14, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 19 months 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.