1. Home
  2. Directory
  3. Illinois
  4. Chicago
  5. Surgery
  6. NPI Profile

MARK LOREN KELDAHL MD
NPI 1114181658
Surgery - Vascular Surgery in Chicago, IL

Active since July 14, 2008PECOS EnrolledAccepts Medicare Assignment
3000 N. HALSTED ST., SUITE 703, CHICAGO, IL 60657(773) 296-3390(773) 296-7531 Get Directions Write a Review

NPPES record last updated: June 25, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Mar 25, 2025, Dec 29, 2021, Apr 1, 2021 (3 updates tracked since 2021).

About Mark Loren Keldahl Md NPPES

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

MARK LOREN KELDAHL MD (NPI 1114181658) is an individual vascular surgery provider in Chicago, Illinois, licensed in Illinois (036-117220) and active in the NPI registry since July 2008. He is enrolled in Medicare PECOS, is affiliated with Advocate Trinity Hospital, and maintains a secondary practice location in Memphis.

NPPES Registry Identity

NPI1114181658
Entity TypeIndividualMale
Primary Taxonomy2086S0129X
Provider Legal NameMARK LOREN KELDAHLCredential: MD
Location Address3000 N. HALSTED ST., SUITE 703Chicago, IL 60657
Mailing Address29373 Network PlChicago, IL 60673-1293 · (847) 390-5900
Phone(773) 296-3390
Fax(773) 296-7531
Sole ProprietorNo
Medical School CMSRush Medical College Of Rush UniversityGraduated 2004
Enumeration DateJuly 14, 2008
Last NPPES UpdateJune 25, 20263 updates tracked since enumeration
NPPES CertifiedJune 25, 2026
✔ NPI 1114181658 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtySurgery · Vascular SurgeryAllopathic & Osteopathic Physicians
Taxonomy Code2086S0129X
Licenses✔ Licensed in IL · 036-117220✔ Licensed in TN · 59517
Definition
A surgeon with expertise in the management of surgical disorders of the blood vessels, excluding the intracranial vessels or the heart.
Also ListedSurgeryTaxonomy 208600000X · License 036-117220 (IL), 036117220 (IL)
3000 N. HALSTED ST., Chicago, IL 60657
Open in Google Maps ↗

Secondary Practice Location 1

Location 11325 Eastmoreland Ave Ste 365Memphis, TN 38104-7542 · Phone (901) 272-6018 · Fax (901) 201-4203

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Ambetter Health, Ambetter Health of Delaware, Oscar Health.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

Mark Loren Keldahl 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 ID7719155381
PECOS Enrollment IDI20110726000565
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 Mark Keldahl reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Advocate Health And Hospitals Corp.
1.0 mi
Cardiovascular Disease
3118 N ASHLAND AVE
Chicago, IL 60657
  • Reassigned Medicare billing, Illinois enrollment
  • 4,870 clinicians in this Medicare group
NPI 1487951711 (773) 880-9722

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 11

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.

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.
346 services63 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.
157 services118 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.
131 services53 patients
New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more 99203
This service involves an initial office or outpatient visit for a new patient. The healthcare professional will spend 30-44 minutes understanding your health history, current issues, and discussing possible treatment plans. It's a comprehensive evaluation to start your healthcare journey.
74 services74 patients
Application of skin substitute graft to wound of trunk, arms, or legs, 25.0 sq cm or less of wound 100.0 sq cm or less 15271
This procedure involves applying a skin substitute graft to a wound on the trunk, arms, or legs. The graft, a lab-grown skin, is used to cover a wound area of 25.0 sq cm or less, within a total wound area of 100.0 sq cm or less. It aids in healing and regeneration.
62 services12 patients
Initial hospital care with straightforward or low level of medical decision making, per day, if using time, at least 40 minutes 99221
Initial hospital inpatient care refers to the first day of your stay in the hospital. This service typically includes a 30-minute check-up with a healthcare professional. They'll assess your health, discuss your condition, and plan your treatment. It's part of ensuring you receive the best possible care.
41 services35 patients

Hospital Affiliations CMS Care Compare 4

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

Advocate Trinity Hospital

Acute Care Hospitals · Chicago, IL
2/5 CMS rating
OwnershipVoluntary non-profit - Other
CMS Certification Number140048
Location2320 E 93rd StChicago, IL 60617 · Cook County
Emergency services Birthing friendly

Advocate Illinois Masonic Medical Center

Acute Care Hospitals · Chicago, IL
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number140182
Location836 West Wellington AvenueChicago, IL 60657 · Cook County
Emergency services Birthing friendly

Advocate Lutheran General Hospital

Acute Care Hospitals · Park Ridge, IL
5/5 CMS rating
OwnershipVoluntary non-profit - Church
CMS Certification Number140223
Location1775 Dempster StPark Ridge, IL 60068 · Cook County
Emergency services Birthing friendly

Advocate Good Samaritan Hospital

Acute Care Hospitals · Downers Grove, IL
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number140288
Location3815 Highland AvenueDowners Grove, IL 60515 · Du Page County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 60657 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
$94.06 typical visit price
range $60.08 – $183.39
Typical copayment $23.51 (range $15.02 – $45.84)
Most-billed visit code 99203
Established Patient
$74.80 typical visit price
range $18.97 – $148.12
Typical copayment $18.70 (range $4.74 – $37.03)
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.

Referred Medical Equipment & Supplies CMS DME claims 2

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

Tape, non-waterproof, per 18 square inches A4450
DME-Medical/Surgical Supplies · category DA000N
1 supplier13 claims528 services$0.10 avg. paid by Medicare
Alginate or other fiber gelling dressing, wound cover, sterile, pad size more than 16 sq. in. but less than or equal to 48 sq. in., each dressing A6197
DME-Medical/Surgical Supplies · category DA023N
1 supplier12 claims649 services$15.90 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

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

KENJI MURO M.D.
Neurological Surgery
3000 N. HALSTED ST., SUITE 703
CHICAGO, IL 60657
Cook County (773) 296-6666

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 Keldahl's NPI number?

The NPI number for Mark Keldahl is 1114181658. It was assigned to this individual provider in the NPPES registry on July 14, 2008.

Where is Mark Keldahl located?

Mark Keldahl practices at 3000 N. Halsted St. Suite 703, Chicago, IL 60657. The listed phone number is (773) 296-3390.

What is Mark Keldahl's specialty?

The primary specialty registered for this NPI is Surgery, specializing in Vascular Surgery, with taxonomy code 2086S0129X.

Is Mark Keldahl enrolled in Medicare?

Yes. Mark Keldahl 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 Mark Keldahl's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Mark Keldahl reassigns Medicare benefits to Advocate Health And Hospitals Corp. (Chicago, IL). 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 Mark Keldahl's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Mark Keldahl accept?

Health plans from Ambetter Health, Ambetter Health of Delaware and Oscar Health list Mark Keldahl 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 Keldahl affiliated with any hospitals?

According to CMS data, Mark Keldahl is affiliated with Advocate Trinity Hospital, Advocate Illinois Masonic Medical Center, Advocate Lutheran General Hospital and Advocate Good Samaritan Hospital.

When was this NPI record last updated?

The NPPES record for Mark Keldahl was last updated on June 25, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 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.