MARK C JOHNSON MD
NPI 1013923127
Internal Medicine in Mason City, IA

Q: What is Mark Johnson's NPI number?

The NPI number for Mark Johnson is 1013923127. It was assigned to this individual provider in the NPPES registry on July 31, 2006.

Q: What is Mark Johnson's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Q: When was this NPI record last updated?

The NPPES record for Mark Johnson was last updated on July 8, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 13 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.

Active since July 31, 2006PECOS EnrolledAccepts Medicare Assignment

910 N EISENHOWER AVE, MASON CITY, IA 50401(641) 428-7799(641) 428-5274 Get Directions Write a Review

NPPES record last updated: July 8, 2025. Verified against the NPPES registry weekly; last sync: August 16, 2026.

Record update history: Jul 8, 2025, Apr 20, 2021, Aug 18, 2020 (3 updates tracked since 2020).

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About Mark C Johnson Md NPPES

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

MARK C JOHNSON MD (NPI 1013923127) is an individual internal medicine provider in Mason City, Iowa, licensed in Iowa (21527) and active in the NPI registry since July 2006. He is enrolled in Medicare PECOS, is affiliated with Mercyone North Iowa Medical Center, and is a graduate of University Of Iowa, Rj & L Carver College Of Medicine (1977).

NPPES Registry Identity

NPI1013923127

Entity TypeIndividualMale

Primary Taxonomy207R00000X

Provider Legal NameMARK C JOHNSONCredential: MD

Location Address910 N EISENHOWER AVEMason City, IA 50401-2800

Mailing Address621 S Illinois Ave, Suite 103Mason City, IA 50401-5489 · (641) 428-3041 · Fax (641) 428-3059

Phone(641) 428-7799

Fax(641) 428-5274

Sole ProprietorNo

Medical School CMSUniversity Of Iowa, Rj & L Carver College Of MedicineGraduated 1977

Enumeration DateJuly 31, 2006

Last NPPES UpdateJuly 8, 20253 updates tracked since enumeration

NPPES CertifiedJuly 8, 2025

✔ NPI 1013923127 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians

Taxonomy Code207R00000X

License✔ Licensed in IA · 21527

Definition

A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.

910 N EISENHOWER AVE, Mason City, IA 50401

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Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Ambetter from Home State Health, Ambetter from NH Healthy Families, 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

Mark C Johnson 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 ID4688678410

PECOS Enrollment IDI20060908000162

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 6

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.

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.

1,381 services1,050 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.

987 services467 patients

Continuous monitoring of blood sugar level in tissue fluid using sensor under skin with interpretation and report 95251

This procedure involves placing a small sensor under your skin to continuously monitor your blood sugar levels in tissue fluid. The data is interpreted and a report is generated to help manage your diabetes more effectively.

379 services184 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.

244 services100 patients

Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214

17 services11 patients

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.

13 services12 patients

Hospital Affiliations CMS Care Compare 5

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

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

Iowa Specialty Hospital - Clarion

Critical Access Hospitals · Clarion, IA

OwnershipGovernment - Local

CMS Certification Number161302

Location1316 South Main StreetClarion, IA 50525 · Wright County

Emergency services Birthing friendly

Hancock County Health System

Critical Access Hospitals · Britt, IA

OwnershipGovernment - Local

CMS Certification Number161307

Location532 1st St NWBritt, IA 50423 · Hancock County

Emergency services

Floyd County Medical Center

Critical Access Hospitals · Charles City, IA

3/5 CMS rating

OwnershipGovernment - Local

CMS Certification Number161347

Location800 11th StCharles City, IA 50616 · Floyd County

Emergency services Birthing friendly

Kossuth Regional Health Center

Critical Access Hospitals · Algona, IA

1/5 CMS rating

OwnershipGovernment - Local

CMS Certification Number161353

Location1515 South Phillips StreetAlgona, IA 50511 · Kossuth 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

$122.23 typical visit price

range $52.96 – $161.40

Typical copayment $30.55 (range $13.24 – $40.35)

Most-billed visit code 99204

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.

Referred Medical Equipment & Supplies CMS DME claims 12

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Supplies for maintenance of insulin infusion catheter, per week A4224

DME-Other DME · category DE017N

14 suppliers94 claims1,125 services$19.10 avg. paid by Medicare

Supplies for external insulin infusion pump, syringe type cartridge, sterile, each A4225

DME-Other DME · category DE017N

15 suppliers99 claims2,876 services$2.38 avg. paid by Medicare

Supply allowance for adjunctive continuous glucose monitor (cgm), includes all supplies and accessories, 1 month supply = 1 unit of service A4238

DME-Medical/Surgical Supplies · category DA000N

3 suppliers22 claims22 services$173.46 avg. paid by Medicare

Blood glucose test or reagent strips for home blood glucose monitor, per 50 strips A4253

DME-Other DME · category DE017N

38 suppliers750 claims1,729 services$6.15 avg. paid by Medicare

Spring-powered device for lancet, each A4258

DME-Other DME · category DE000N

6 suppliers11 claims11 services$1.79 avg. paid by Medicare

Lancets, per box of 100 A4259

DME-Medical/Surgical Supplies · category DA000N

27 suppliers180 claims215 services$1.02 avg. paid by Medicare

Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

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.

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