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MR. SERGEY L ISTOMIN CRNP, PMHNP-BC
NPI 1023384963
Nurse Practitioner - Psychiatric/Mental Health in Bethesda, MD

Active since March 26, 2012PECOS Enrolled
6040 SOUTHPORT DR, BETHESDA, MD 20814(301) 493-4200 Get Directions Write a Review

NPPES record last updated: December 3, 2013. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Mr. Sergey L Istomin Crnp, Pmhnp-bc NPPES

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

MR. SERGEY L ISTOMIN CRNP, PMHNP-BC (NPI 1023384963) is an individual psychiatric/mental health provider in Bethesda, Maryland, licensed in Maryland (R208690) and active in the NPI registry since March 2012. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1023384963
Entity TypeIndividualMale
Primary Taxonomy363LP0808X
Provider Legal NameMR. SERGEY L ISTOMINCredential: CRNP, PMHNP-BC
Location Address6040 SOUTHPORT DRBethesda, MD 20814-1848
Mailing Address6040 Southport DrBethesda, MD 20814-1848 · (301) 493-4200
Phone(301) 493-4200
Sole ProprietorNo
Enumeration DateMarch 26, 2012
Last NPPES UpdateDecember 3, 2013
✔ NPI 1023384963 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyNurse Practitioner · Psychiatric/Mental HealthPhysician Assistants & Advanced Practice Nursing Providers
Taxonomy Code363LP0808X
License✔ Licensed in MD · R208690
6040 SOUTHPORT DR, Bethesda, MD 20814
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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 (PECOS)

Mr. Sergey L Istomin Crnp, Pmhnp-bc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

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

2

Medicare enrollment records show Sergey Istomin reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Cornerstone Montgomery, Inc.
Same address
Mental Health (Including Community Mental Health Center)
6040 SOUTHPORT DR
Bethesda, MD 20814
  • Reassigned Medicare billing, District of Columbia enrollment
  • 51 clinicians in this Medicare group
NPI 1194725739 (301) 493-4200
Chase Brexton Health Services, Inc.
33 mi
Federally Qualified Health Center (FQHC)
1111 NORTH CHARLES STREET
Baltimore, MD 21201
  • Reassigned Medicare billing, Maryland enrollment
  • 213 clinicians in this Medicare group
NPI 1588606305 (410) 837-2050

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 7

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.

Psychotherapy, 45 minutes 90834
Psychotherapy is a treatment method where you converse with a therapist about your thoughts, feelings, and behaviors. In a 45-minute session, the therapist assists you in understanding and managing your mental health concerns, improving emotional wellness, and promoting personal growth.
125 services64 patients
Psychotherapy, 30 minutes 90832
Psychotherapy is a therapeutic interaction or treatment between a trained professional and a patient. In a 30-minute session, the therapist helps you explore feelings, thoughts, and behaviors to better understand yourself and manage life's challenges.
77 services54 patients
Telephone medical discussion with physician, 21-30 minutes 99443
This service involves a 21-30 minute phone conversation with a physician. It's a chance for you to discuss your health concerns, symptoms or treatment plans. It's similar to an in-person consultation, but conducted over the phone for your convenience and safety.
59 services37 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.
53 services34 patients
Injection of drug or substance under skin or into muscle 96372
This procedure involves administering medication directly under the skin or into a muscle. A small needle is used to inject the drug, allowing it to be absorbed quickly into the bloodstream. It's a common method for delivering a variety of medications.
37 services26 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.
34 services23 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 20814 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
$100.31 typical visit price
range $65.18 – $194.86
Typical copayment $25.07 (range $16.29 – $48.71)
Most-billed visit code 99203
Established Patient
$113.72 typical visit price
range $21.40 – $158.88
Typical copayment $28.43 (range $5.35 – $39.72)
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.

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.

MRS. GEORGIA CHIPOURAS MUNSON LCSW-C
Social Worker (Clinical)
6040 SOUTHPORT DR
BETHESDA, MD 20814
Montgomery County (301) 493-4200
MRS. LOUISA AMANDA EID
Social Worker (Clinical)
6040 SOUTHPORT DR
BETHESDA, MD 20814
Montgomery County (301) 493-4200
IJAZ KHAN M.D.
Psychiatry & Neurology (Psychiatry)
6040 SOUTHPORT DR
BETHESDA, MD 20814
Montgomery County (301) 493-4200
NATHANIEL M IDEHEN
Registered Nurse
6040 SOUTHPORT DR
BETHESDA, MD 20814
Montgomery County (301) 493-4200
MRS. JENNIFER EKUNDAYO JACKSON-BICKERSTETH LPN
Licensed Practical Nurse
6040 SOUTHPORT DR
BETHESDA, MD 20814
Montgomery County (301) 715-3673
KATHLEEN KIRK
Social Worker
6040 SOUTHPORT DR
BETHESDA, MD 20814
Montgomery County (301) 493-4200
AUDRIAN GRAEME FLORY
Social Worker
6040 SOUTHPORT DR
BETHESDA, MD 20814
Montgomery County (240) 281-4185
CLARISSA FOXLEY M.A, LGPC, NCC
Counselor (Mental Health)
6040 SOUTHPORT DR
BETHESDA, MD 20814
Montgomery County (202) 306-9377

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 Sergey Istomin's NPI number?

The NPI number for Sergey Istomin is 1023384963. It was assigned to this individual provider in the NPPES registry on March 26, 2012.

Where is Sergey Istomin located?

Sergey Istomin practices at 6040 Southport Dr, Bethesda, MD 20814. The listed phone number is (301) 493-4200.

What is Sergey Istomin's specialty?

The primary specialty registered for this NPI is Nurse Practitioner, specializing in Psychiatric/Mental Health, with taxonomy code 363LP0808X.

Is Sergey Istomin enrolled in Medicare?

Yes. Sergey Istomin is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Sergey Istomin's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Sergey Istomin reassigns Medicare benefits to 2 organizations: Cornerstone Montgomery, Inc. (Bethesda, MD) and Chase Brexton Health Services, Inc. (Baltimore, MD). 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 Sergey Istomin's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for Sergey Istomin was last updated on December 3, 2013. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 12 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.