MR. MARK I CHIEH HONG M.D
NPI 1982048286
Internal Medicine - Nephrology in Mason City, IA

Q: What is Mark Hong's NPI number?

The NPI number for Mark Hong is 1982048286. It was assigned to this individual provider in the NPPES registry on April 17, 2013. The provider is also known as I Chieh Hong M.D.

Q: What is Mark Hong's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Nephrology, with taxonomy code 207RN0300X.

Q: When was this NPI record last updated?

The NPPES record for Mark Hong was last updated on July 15, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 15 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 April 17, 2013PECOS EnrolledAccepts Medicare Assignment

1000 4TH ST SW, MASON CITY, IA 50401(641) 428-6999(641) 428-6678 Get Directions Write a Review

NPPES record last updated: July 15, 2025. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Jan 5, 2024, Sep 30, 2022, May 21, 2021 and 1 more (4 updates tracked since 2020).

On this page

About Mr. Mark I Chieh Hong M.d NPPES

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

MR. MARK I CHIEH HONG M.D (NPI 1982048286) is an individual nephrology provider in Mason City, Iowa, licensed in Iowa (42588) and active in the NPI registry since April 2013. He is enrolled in Medicare PECOS, is affiliated with Mercyone North Iowa Medical Center, and is a graduate of Other (2010).

NPPES Registry Identity

NPI1982048286

Entity TypeIndividualMale

Primary Taxonomy207RN0300X

Provider Legal NameMR. MARK I CHIEH HONGCredential: M.D

Location Address1000 4TH ST SWMason City, IA 50401-2800

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

Phone(641) 428-6999

Fax(641) 428-6678

Sole ProprietorNo

Medical School CMSOtherGraduated 2010

Enumeration DateApril 17, 2013

Last NPPES UpdateJuly 15, 20254 updates tracked since enumeration

NPPES CertifiedJuly 15, 2025

✔ NPI 1982048286 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal Medicine · NephrologyAllopathic & Osteopathic Physicians

Taxonomy Code207RN0300X

License✔ Licensed in IA · 42588

Definition

An internist who treats disorders of the kidney, high blood pressure, fluid and mineral balance and dialysis of body wastes when the kidneys do not function. This specialist consults with surgeons about kidney transplantation.

Also ListedStudent in an Organized Health Care Education/Training ProgramTaxonomy 390200000X

1000 4TH ST SW, Mason City, IA 50401

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Other Names 1

Former Name (1)I Chieh Hong M.d

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Ambetter from NH Healthy Families, Ambetter from Sunflower Health Plan, Ambetter Health and more.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

Mr. Mark I Chieh Hong M.d 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 ID7113239096

PECOS Enrollment IDI20150707000676

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 Mark Hong reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

North Iowa Mercy Clinics

Same address

Nurse Practitioner

1000 4TH ST SW
Mason City, IA 50401

Reassigned Medicare billing, Iowa enrollment
420 clinicians in this Medicare group

NPI 1043321102 (641) 428-5932

Hancock County Health System

30 mi

Family Medicine

532 1ST ST NW
Britt, IA 50423

Reassigned Medicare billing, Iowa enrollment
Also billed through NPI 1912938606 (Iowa)
50 clinicians in this Medicare group

NPI 1144434283 (641) 843-5000

Cogent Healthcare Of Iowa, PC

114 mi

Internal Medicine

701 10TH ST SE
Cedar Rapids, IA 52403

Reassigned Medicare billing, Iowa enrollment
153 clinicians in this Medicare group

NPI 1982654497 (319) 861-7803

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 19

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.

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.

857 services175 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.

201 services176 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.

188 services118 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.

166 services124 patients

Home dialysis services per month (20 years or older) 90966

Home dialysis services provide kidney treatment for patients aged 20 or older right in their own homes. This service includes necessary equipment, supplies, and support for performing dialysis. It's a convenient option that allows patients to maintain their daily routines while receiving essential care.

130 services19 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.

93 services37 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.

78 services48 patients

Dialysis services, 2-3 physician visits per month (20 years or older) 90961

Dialysis is a treatment that performs the function of healthy kidneys if they're not working properly. It removes waste and excess fluid from your blood. 2-3 physician visits per month are recommended for monitoring your health and adjusting your treatment as needed. This service is available for those aged 20 years and older.

73 services18 patients

Subsequent nursing facility care with straightforward level of medical decision making, per day, if using time, at least 10 minutes 99307

A follow-up nursing facility visit per day typically lasts about 10 minutes. This service involves a healthcare professional checking on your health status, answering any questions you may have, and monitoring your progress. This routine check ensures your recovery is on track and any concerns are addressed promptly.

48 services28 patients

Dialysis services, 4 or more physician visits per month (20 years or older) 90960

Dialysis is a treatment that filters and purifies your blood using a machine. It helps keep your fluids and electrolytes in balance when the kidneys can't do their job. This service includes 4 or more visits per month with a physician to monitor your health and adjust your treatment as needed.

47 services16 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.

39 services37 patients

Hospital discharge day management, more than 30 minutes 99239

Hospital discharge day management over 30 minutes involves a detailed process to ensure a smooth transition from hospital to home. It includes final examinations, discussion of your hospital stay, post-discharge instructions, and coordinating follow-up care.

30 services30 patients

Hospital discharge day management, 30 minutes or less 99238

Hospital discharge day management of 30 minutes or less includes finalizing your treatment, discussing your progress, and planning after-care at home. It ensures you're ready to leave the hospital and continue recovery safely.

24 services24 patients

Initial nursing facility care with moderate level of medical decision making, per day, if using time, at least 35 minutes 99305

An initial nursing facility visit per day is a service where a healthcare professional spends about 35 minutes assessing a patient's health status. This includes reviewing medical history, conducting a physical exam, and developing a care plan based on the patient's needs.

19 services19 patients

Subsequent nursing facility care with straightforward level of medical decision making, per day, if using time, 20 minutes or more 99308

A follow-up nursing facility visit per day is a daily check-up service provided by healthcare professionals. It lasts around 15 minutes and involves assessing your health status, monitoring your recovery progress, and addressing any concerns you may have about your health or treatment.

19 services15 patients

Nursing facility discharge day management, 30 minutes or less 99315

Nursing facility discharge day management involves organizing your transition from the nursing facility to your home or another facility. This service, taking 30 minutes or less, includes finalizing medical instructions, arranging follow-up care, and answering any questions.

19 services18 patients

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.

17 services11 patients

Nursing facility discharge management, more than 30 minutes 99316

Nursing facility discharge management over 30 minutes is a comprehensive process where a healthcare team prepares you for leaving the facility. It involves creating a tailored plan, coordinating care, and ensuring a smooth transition to your next care setting.

14 services14 patients

Initial nursing facility care with high level of medical decision making, per day, if using time, 50 minutes or more 99306

An initial nursing facility visit is your first meeting with your healthcare team at a nursing facility. Lasting typically 45 minutes, this appointment involves a comprehensive health assessment and the creation of your personalized care plan. It's a crucial step to ensure your health and well-being.

12 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

Hancock County Health System

Critical Access Hospitals · Britt, IA

OwnershipGovernment - Local

CMS Certification Number161307

Location532 1st St NWBritt, IA 50423 · Hancock County

Emergency services

Franklin General Hospital

Critical Access Hospitals · Hampton, IA

OwnershipGovernment - Local

CMS Certification Number161308

Location1720 Central Avenue EastHampton, IA 50441 · Franklin County

Emergency services

Mitchell County Regional Health

Critical Access Hospitals · Osage, IA

OwnershipGovernment - Local

CMS Certification Number161323

Location616 North Eighth StreetOsage, IA 50461 · Mitchell County

Emergency services

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 10

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

Portable gaseous oxygen system, rental; includes portable container, regulator, flowmeter, humidifier, cannula or mask, and tubing E0431

DME-Oxygen and Supplies · category DC000N

2 suppliers13 claims13 services$21.27 avg. paid by Medicare

Oxygen concentrator, single delivery port, capable of delivering 85 percent or greater oxygen concentration at the prescribed flow rate E1390

DME-Oxygen and Supplies · category DC002N

2 suppliers40 claims40 services$104.02 avg. paid by Medicare

Portable oxygen concentrator, rental E1392

DME-Oxygen and Supplies · category DC002N

1 supplier27 claims27 services$33.50 avg. paid by Medicare

Tacrolimus, immediate release, oral, 1 mg J7507

Treatment-Treatment - Miscellaneous · category RX029N

5 suppliers30 claims1,320 services$0.29 avg. paid by Medicare

Prednisone, immediate release or delayed release, oral, 1 mg J7512

Treatment-Treatment - Miscellaneous · category RX029N

1 supplier13 claims1,470 services$0.01 avg. paid by Medicare

Cyclosporine, oral, 25 mg J7515

Treatment-Treatment - Miscellaneous · category RX029N

2 suppliers21 claims1,890 services$0.54 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.

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 Mark Hong's NPI number?

The NPI number for Mark Hong is 1982048286. It was assigned to this individual provider in the NPPES registry on April 17, 2013. The provider is also known as I Chieh Hong M.D.

Where is Mark Hong located?

Mark Hong practices at 1000 4th St SW, Mason City, IA 50401. The listed phone number is (641) 428-6999.

What is Mark Hong's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Nephrology, with taxonomy code 207RN0300X.

Is Mark Hong enrolled in Medicare?

Yes. Mark Hong 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 Mark Hong's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Mark Hong reassigns Medicare benefits to 3 organizations: North Iowa Mercy Clinics (Mason City, IA), Hancock County Health System (Britt, IA) and Cogent Healthcare Of Iowa, PC (Cedar Rapids, IA). 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 Mark Hong's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Mark Hong accept?

Health plans from Ambetter Health, Ambetter Health of Delaware, Ambetter from NH Healthy Families, Ambetter from Sunflower Health Plan and Oscar Insurance Company and 1 other insurer list Mark Hong 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 Hong affiliated with any hospitals?

According to CMS data, Mark Hong is affiliated with Mercyone North Iowa Medical Center, Hancock County Health System, Franklin General Hospital, Mitchell County Regional Health and Kossuth Regional Health Center.

When was this NPI record last updated?

The NPPES record for Mark Hong was last updated on July 15, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 15 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.