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WILLIAM I PARKER MD
NPI 1356459903
Emergency Medicine in Mason City, IA

Active since August 25, 2006PECOS EnrolledAccepts Medicare Assignment
1000 4TH ST SW, SUITE ER, MASON CITY, IA 50401(641) 422-7234(641) 422-6373 Get Directions Write a Review

NPPES record last updated: October 11, 2023. Verified against the NPPES registry weekly; last sync: August 09, 2026.

About William I Parker Md NPPES

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

WILLIAM I PARKER MD (NPI 1356459903) is an individual emergency medicine provider in Mason City, Iowa, licensed in Iowa (28723) and active in the NPI registry since August 2006. He is enrolled in Medicare PECOS, is affiliated with Hca Florida Lake City Hospital, and is a graduate of Other (1991).

NPPES Registry Identity

NPI1356459903
Entity TypeIndividualMale
Primary Taxonomy207P00000X
Provider Legal NameWILLIAM I PARKERCredential: MD
Location Address1000 4TH ST SW, SUITE ERMason City, IA 50401-2800
Mailing Address621 S Illinois Ave, Suite 103Mason City, IA 50401-5489 · (641) 494-3041 · Fax (641) 494-3059
Phone(641) 422-7234
Fax(641) 422-6373
Sole ProprietorNo
Medical School CMSOtherGraduated 1991
Enumeration DateAugust 25, 2006
Last NPPES UpdateOctober 11, 2023
NPPES CertifiedOctober 11, 2023
✔ NPI 1356459903 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyEmergency MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207P00000X
License✔ Licensed in IA · 28723
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.
1000 4TH ST SW, Mason City, IA 50401
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Other Identifiers 2

Medicaid2073189IA
Other47792IA · Wellmark

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Medica, Oscar Insurance Company.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

William I Parker 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 ID6800783044
PECOS Enrollment IDI20250203003538
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 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 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.
216 services207 patients
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.
83 services81 patients
Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only 93010
A routine electrocardiogram (ECG) with 12 leads is a simple, non-invasive test that records the electrical activity of your heart. It helps in identifying heart conditions by detecting irregularities in your heart rhythms. The results are interpreted and a report is provided.
14 services14 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.
13 services13 patients

Hospital Affiliations CMS Care Compare 3

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

Hca Florida Lake City Hospital

Acute Care Hospitals · Lake City, FL
3/5 CMS rating
OwnershipProprietary
CMS Certification Number100156
Location340 NW Commerce DrLake City, FL 32055 · Columbia County
Emergency services

Hca Florida Englewood Hospital

Acute Care Hospitals · Englewood, FL
3/5 CMS rating
OwnershipProprietary
CMS Certification Number100267
Location700 Medical BlvdEnglewood, FL 34223 · Sarasota County
Emergency services

Mercyone North Iowa Medical Center

Acute Care Hospitals · Mason City, IA
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number160064
Location1000 Fourth Street SWMason City, IA 50401 · Cerro Gordo County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 50401 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
$81.84 typical visit price
range $52.96 – $161.40
Typical copayment $20.46 (range $13.24 – $40.35)
Most-billed visit code 99203
Established Patient
$94.05 typical visit price
range $16.91 – $131.98
Typical copayment $23.51 (range $4.22 – $32.99)
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.

LINDA S VOLD LISW
Social Worker (Clinical)
1000 4TH ST SW, SUITE BS
MASON CITY, IA 50401
Cerro Gordo County (641) 422-7797
BURT HUMBURG MD
Internal Medicine
1000 4TH ST SW
MASON CITY, IA 50401
Cerro Gordo County (641) 428-7000
SUMATHY NAGRAJ IYENGAR M.D.,
Hospitalist
1000 4TH ST SW, MERCY MEDICAL CENTER-HOSPITALIST DEPT
MASON CITY, IA 50401
Cerro Gordo County (641) 428-7000
DR. SATINDERJIT SINGH M.D.
Emergency Medicine
1000 4TH ST SW
MASON CITY, IA 50401
Cerro Gordo County (641) 428-7234
ASHLEY MATERN ARNP
Nurse Practitioner (Family)
1000 4TH ST SW
MASON CITY, IA 50401
Cerro Gordo County (641) 428-6999
ROBERT D. FROEHNER CRNA
Nurse Anesthetist, Certified Registered
1000 4TH ST SW
MASON CITY, IA 50401
Cerro Gordo County (641) 422-7000
DR. THOMAS P DELANEY MD
Hospitalist
1000 4TH ST SW, SUITE HOSP
MASON CITY, IA 50401
Cerro Gordo County (641) 422-7000
NORTH IOWA MERCY CLINICS
Nurse Practitioner
1000 4TH ST SW
MASON CITY, IA 50401
Cerro Gordo County (641) 428-5932

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 Parker's NPI number?

The NPI number for William Parker is 1356459903. It was assigned to this individual provider in the NPPES registry on August 25, 2006.

Where is William Parker located?

William Parker practices at 1000 4th St SW Suite ER, Mason City, IA 50401. The listed phone number is (641) 422-7234.

What is William Parker's specialty?

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

Is William Parker enrolled in Medicare?

Yes. William Parker 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 William Parker accept?

Health plans from Medica and Oscar Insurance Company list William Parker 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 William Parker affiliated with any hospitals?

According to CMS data, William Parker is affiliated with Hca Florida Lake City Hospital, Hca Florida Englewood Hospital and Mercyone North Iowa Medical Center.

When was this NPI record last updated?

The NPPES record for William Parker was last updated on October 11, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 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.