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DR. MICHAEL NMN GRASSIA MD
NPI 1235128133
Internal Medicine - Nephrology in Norfolk, VA

Active since October 14, 2005PECOS EnrolledAccepts Medicare Assignment
67.42/100
CMS Quality Rating
6160 KEMPSVILLE CIRCLE, SUITE 302A, NORFOLK, VA 23502(757) 466-9288(757) 457-3691 Get Directions Write a Review

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

About Dr. Michael Nmn Grassia Md NPPES

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

DR. MICHAEL NMN GRASSIA MD (NPI 1235128133) is an individual nephrology provider in Norfolk, Virginia, licensed in Virginia (0101232951) and active in the NPI registry since October 2005. He is enrolled in Medicare PECOS, is affiliated with Riverside Shore Memorial Hospital, and is a graduate of Eastern Virginia Medical School (1997).

NPPES Registry Identity

NPI1235128133
Entity TypeIndividualMale
Primary Taxonomy207RN0300X
Provider Legal NameDR. MICHAEL NMN GRASSIACredential: MD
Location Address6160 KEMPSVILLE CIRCLE, SUITE 302ANorfolk, VA 23502-3933
Mailing Address6160 Kempsville Circle, Suite 302aNorfolk, VA 23502-3933 · (757) 466-9288 · Fax (757) 457-3691
Phone(757) 466-9288
Fax(757) 457-3691
Sole ProprietorNo
Medical School CMSEastern Virginia Medical SchoolGraduated 1997
Enumeration DateOctober 14, 2005
Last NPPES UpdateOctober 25, 2007
✔ NPI 1235128133 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · NephrologyAllopathic & Osteopathic Physicians
Taxonomy Code207RN0300X
License✔ Licensed in VA · 0101232951
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.
6160 KEMPSVILLE CIRCLE, Norfolk, VA 23502
Open in Google Maps ↗

Other Identifiers 4

Medicaid005875072VA
Medicare PIN390000213
Medicare UPINH62745
Other390008345VA · Railroad Medicare

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. Michael Nmn Grassia 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 ID2961458062
PECOS Enrollment IDI20101013000505
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 Reassignment

Medicare enrollment records show Michael Grassia reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Nephrology Associates Of Tidewater Ltd
0.2 mi
Nephrology
6261 E VIRGINIA BEACH BLVD STE 201
Norfolk, VA 23502
  • Reassigned Medicare billing, Virginia enrollment
  • 31 clinicians in this Medicare group
NPI 1518990423 (757) 466-9288

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 9

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.
609 services215 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.
288 services35 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.
158 services140 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.
149 services117 patients
Chronic care management services, first 20 minutes of clinical staff time directed by health care professional, per calendar month 99490
Chronic care management services involve a healthcare professional directing clinical staff in managing your chronic conditions. This includes the first 20 minutes per month of services like medication management, care coordination, and health monitoring to help improve your health and quality of life.
134 services50 patients
Dialysis services, per day, less than full month service (20 years or older) 90970
Dialysis is a treatment that replicates some functions of healthy kidneys when they're not working properly. It helps to remove waste, salt, and excess water from your body and maintain a safe level of certain chemicals in your blood. This service, for patients aged 20 or older, is provided on a daily basis for less than a full month.
79 services16 patients

Hospital Affiliations CMS Care Compare 5

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

Riverside Shore Memorial Hospital

Acute Care Hospitals · Onancock, VA
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number490037
Location20480 Market StreetOnancock, VA 23417 · Accomack County
Emergency services Birthing friendly

Sentara Leigh Hospital

Acute Care Hospitals · Norfolk, VA
4/5 CMS rating
OwnershipVoluntary non-profit - Other
CMS Certification Number490046
Location830 Kempsville RoadNorfolk, VA 23502 · Norfolk City County
Birthing friendly

Sentara Virginia Beach General Hospital

Acute Care Hospitals · Virginia Beach, VA
4/5 CMS rating
OwnershipVoluntary non-profit - Other
CMS Certification Number490057
Location1060 First Colonial RoadVirginia Beach, VA 23454 · Virginia Beach City County
Emergency services

Sentara Princess Anne Hospital

Acute Care Hospitals · Virginia Beach, VA
4/5 CMS rating
OwnershipVoluntary non-profit - Other
CMS Certification Number490119
Location2025 Glenn Mitchell DriveVirginia Beach, VA 23456 · Virginia Beach City County
Birthing friendly

Chesapeake General Hospital

Acute Care Hospitals · Chesapeake, VA
3/5 CMS rating
OwnershipGovernment - Hospital District or Authority
CMS Certification Number490120
Location736 Battlefield Blvd, NorthChesapeake, VA 23320 · Chesapeake City County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 23502 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
$129.04 typical visit price
range $56.19 – $170.30
Typical copayment $32.26 (range $14.04 – $42.57)
Most-billed visit code 99204
Established Patient
$99.13 typical visit price
range $18.07 – $138.91
Typical copayment $24.78 (range $4.51 – $34.72)
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.

67.42/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Scored as part of a group practice
Quality74.29
Promoting Interoperability0
Improvement Activities40
Cost83.8

Referred Medical Equipment & Supplies CMS DME claims 6

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

Tacrolimus, immediate release, oral, 1 mg J7507
Treatment-Treatment - Miscellaneous · category RX029N
4 suppliers29 claims4,740 services$0.31 avg. paid by Medicare
Prednisone, immediate release or delayed release, oral, 1 mg J7512
Treatment-Treatment - Miscellaneous · category RX029N
4 suppliers22 claims3,300 services$0.01 avg. paid by Medicare
Cyclosporine, oral, 25 mg J7515
Treatment-Treatment - Miscellaneous · category RX029N
2 suppliers11 claims1,320 services$0.55 avg. paid by Medicare
Mycophenolate mofetil, oral, 250 mg J7517
Treatment-Treatment - Miscellaneous · category RX029N
3 suppliers13 claims1,440 services$0.19 avg. paid by Medicare
Pharmacy supply fee for oral anti-cancer, oral anti-emetic or immunosuppressive drug(s); for the first prescription in a 30-day period Q0511
Treatment-Chemotherapy · category RH012N
5 suppliers34 claims34 services$17.85 avg. paid by Medicare
Pharmacy supply fee for oral anti-cancer, oral anti-emetic or immunosuppressive drug(s); for a subsequent prescription in a 30-day period Q0512
Treatment-Chemotherapy · category RH012N
5 suppliers35 claims51 services$11.40 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 3

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

DR. FRANK WINSTON GWATHMEY M.D.
Orthopaedic Surgery (Hand Surgery)
6160 KEMPSVILLE CIRCLE, SUITE 102A
NORFOLK, VA 23502
Norfolk City (757) 461-8300
SPINE AND ORTHOPEDIC PAIN CENTER
Physical Medicine & Rehabilitation
6160 KEMPSVILLE CIRCLE, SUITE 303A
NORFOLK, VA 23502
Norfolk City (757) 333-3360
CHRISTY SOREY
Nurse Practitioner (Family)
6160 KEMPSVILLE CIRCLE, STE 325 A
NORFOLK, VA 23502
Norfolk City (757) 354-2885

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 Michael Grassia's NPI number?

The NPI number for Michael Grassia is 1235128133. It was assigned to this individual provider in the NPPES registry on October 14, 2005.

Where is Michael Grassia located?

Michael Grassia practices at 6160 Kempsville Circle Suite 302A, Norfolk, VA 23502. The listed phone number is (757) 466-9288.

What is Michael Grassia's specialty?

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

Is Michael Grassia enrolled in Medicare?

Yes. Michael Grassia 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 organization bills Medicare for Michael Grassia's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Michael Grassia reassigns Medicare benefits to Nephrology Associates Of Tidewater Ltd (Norfolk, VA). The 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 Michael Grassia's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

Is Michael Grassia affiliated with any hospitals?

According to CMS data, Michael Grassia is affiliated with Riverside Shore Memorial Hospital, Sentara Leigh Hospital, Sentara Virginia Beach General Hospital, Sentara Princess Anne Hospital and Chesapeake General Hospital.

When was this NPI record last updated?

The NPPES record for Michael Grassia was last updated on October 25, 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.