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MARK R. OTTOLIN M.D.
NPI 1265525729
Internal Medicine - Cardiovascular Disease in Naperville, IL

Active since October 02, 2006PECOS Enrolled
100 SPALDING DRIVE, SUITE 212, NAPERVILLE, IL 60504(630) 357-4111(630) 357-4644 Get Directions Write a Review

NPPES record last updated: September 24, 2021. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Sep 24, 2021, May 24, 2019 (2 updates tracked since 2019).

About Mark R. Ottolin M.d. NPPES

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

MARK R. OTTOLIN M.D. (NPI 1265525729) is an individual cardiovascular disease provider in Naperville, Illinois, licensed in Illinois (036-064112) and active in the NPI registry since October 2006. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1265525729
Entity TypeIndividualMale
Primary Taxonomy207RC0000X
Provider Legal NameMARK R. OTTOLINCredential: M.D.
Location Address100 SPALDING DRIVE, SUITE 212Naperville, IL 60504-6552
Mailing Address1860 Paysphere CirChicago, IL 60674-0018 · (630) 469-9200
Phone(630) 357-4111
Fax(630) 357-4644
Sole ProprietorNo
Enumeration DateOctober 2, 2006
Last NPPES UpdateSeptember 24, 20212 updates tracked since enumeration
NPPES CertifiedSeptember 24, 2021
✔ NPI 1265525729 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Cardiovascular DiseaseAllopathic & Osteopathic Physicians
Taxonomy Code207RC0000X
License✔ Licensed in IL · 036-064112
Definition
An internist who specializes in diseases of the heart and blood vessels and manages complex cardiac conditions such as heart attacks and life-threatening, abnormal heartbeat rhythms.
100 SPALDING DRIVE, Naperville, IL 60504
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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)

Mark R. Ottolin M.d. 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

5

Medicare enrollment records show Mark Ottolin reassigns Medicare billing to 5 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Edward Hospital
0.1 mi
General Acute Care Hospital
801 S WASHINGTON ST
Naperville, IL 60540
  • Reassigned Medicare billing, Illinois enrollment
  • 268 clinicians in this Medicare group
NPI 1013969013 (630) 655-0450
Naperville Psychiatric Ventures
0.3 mi
Psychiatric Hospital
801 S WASHINGTON ST
Naperville, IL 60540
  • Reassigned Medicare billing, Illinois enrollment
  • 61 clinicians in this Medicare group
NPI 1871628362 (630) 305-5500
Central Dupage Hospital Association
7.7 mi
General Acute Care Hospital
25 NORTH WINFIELD RD.
Winfield, IL 60190
  • Reassigned Medicare billing, Illinois enrollment
  • 129 clinicians in this Medicare group
NPI 1003864810 (630) 933-1600
Dupage Medical Group Ltd
8.6 mi
Multi-Specialty
1100 W 31ST ST, STE 300
Downers Grove, IL 60515
  • Reassigned Medicare billing, Illinois enrollment
  • 1,061 clinicians in this Medicare group
NPI 1801833983 (630) 469-9200
Elmhurst Memorial Hospital
13 mi
General Acute Care Hospital
155 E BRUSH HILL RD
Elmhurst, IL 60126
  • Reassigned Medicare billing, Illinois enrollment
  • 205 clinicians in this Medicare group
NPI 1548306343 (331) 221-1000

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 60504 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
$137.43 typical visit price
range $59.81 – $181.38
Typical copayment $34.35 (range $14.95 – $45.34)
Most-billed visit code 99204
Established Patient
$74.38 typical visit price
range $19.15 – $147.12
Typical copayment $18.59 (range $4.78 – $36.78)
Most-billed visit code 99213
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

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 Ottolin's NPI number?

The NPI number for Mark Ottolin is 1265525729. It was assigned to this individual provider in the NPPES registry on October 2, 2006.

Where is Mark Ottolin located?

Mark Ottolin practices at 100 Spalding Drive Suite 212, Naperville, IL 60504. The listed phone number is (630) 357-4111.

What is Mark Ottolin's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Cardiovascular Disease, with taxonomy code 207RC0000X.

Is Mark Ottolin enrolled in Medicare?

Yes. Mark Ottolin is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Mark Ottolin's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Mark Ottolin reassigns Medicare benefits to 5 organizations: Edward Hospital (Naperville, IL), Naperville Psychiatric Ventures (Naperville, IL), Central Dupage Hospital Association (Winfield, IL), Dupage Medical Group Ltd (Downers Grove, IL) and Elmhurst Memorial Hospital (Elmhurst, IL). 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 Ottolin'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 Mark Ottolin was last updated on September 24, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 5 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.