Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 60 days.

DR. TIMOTHY L GILLISON MD
NPI 1710905906
Internal Medicine - Hematology & Oncology in Chicago, IL

Q: What is Timothy Gillison's NPI number?

The NPI number for Timothy Gillison is 1710905906. It was assigned to this individual provider in the NPPES registry on July 17, 2006.

Q: What is Timothy Gillison's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Hematology & Oncology, with taxonomy code 207RH0003X.

Q: When was this NPI record last updated?

The NPPES record for Timothy Gillison was last updated on October 9, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 19 days 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 July 17, 2006PECOS EnrolledAccepts Medicare Assignment

75/100

CMS Quality Rating

5841 S MARYLAND AVE, CHICAGO, IL 60637(888) 824-0200 Get Directions Write a Review

NPPES record last updated: October 9, 2026. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Oct 9, 2026, May 22, 2020 (2 updates tracked since 2020).

On this page

About Dr. Timothy L Gillison Md NPPES

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

DR. TIMOTHY L GILLISON MD (NPI 1710905906) is an individual hematology & oncology provider in Chicago, Illinois, licensed in Illinois (036125875) and active in the NPI registry since July 2006. He is enrolled in Medicare PECOS, is affiliated with The University Of Chicago Medical Center, and maintains 2 additional practice locations.

NPPES Registry Identity

NPI1710905906

Entity TypeIndividualMale

Primary Taxonomy207RH0003X

Provider Legal NameDR. TIMOTHY L GILLISONCredential: MD

Location Address5841 S MARYLAND AVEChicago, IL 60637-1443

Mailing Address150 Harvester Dr Ste 300Burr Ridge, IL 60527-5965 · (888) 824-0200

Phone(888) 824-0200

Sole ProprietorNo

Medical School CMSSouthern Illinois University School Of MedicineGraduated 2003

Enumeration DateJuly 17, 2006

Last NPPES UpdateOctober 9, 20262 updates tracked since enumeration

NPPES CertifiedOctober 9, 2026

✔ NPI 1710905906 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Hematology & OncologyAllopathic & Osteopathic Physicians

Taxonomy Code207RH0003X

Licenses✔ Licensed in IL · 036125875✔ Licensed in IN · 01061912A

Definition

An internist doctor of osteopathy that specializes in the treatment of the combination of hematology and oncology disorders. A doctor of osteopathy that is board eligible/certified by the American Osteopathic Board of Internal Medicine WAS able to obtain a Certificate of Special Qualifications in the field of Hematology and Oncology. The Certificate is NO longer offered.

5841 S MARYLAND AVE, Chicago, IL 60637

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Secondary Practice Locations 2

Location 1900 N. 1st StreetSpringfield, IL 62702-3749 · Phone (217) 528-7541 · Fax (217) 527-2830

Location 210855 Virginia StCrown Point, IN 46307-0210 · Phone (888) 824-0200

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

Dr. Timothy L Gillison 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 ID2062411572

PECOS Enrollment IDI20110114000559

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 Timothy Gillison reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

The University Of Chicago Medical Center

Same address

General Acute Care Hospital

5841 S MARYLAND AVE
Chicago, IL 60637

Reassigned Medicare billing, Illinois enrollment
1,905 clinicians in this Medicare group

NPI 1033218128 (773) 702-1530

University Of Chicago

Same address

Multi-Specialty

5841 S MARYLAND AVE, UCPG/MC 1099
Chicago, IL 60637

Reassigned Medicare billing, Illinois enrollment
2,237 clinicians in this Medicare group

NPI 1821048786 (773) 702-9200

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 27

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.

Injection, iron sucrose, 1 mg J1756

Iron sucrose injection is a treatment given to replenish iron in your body, often used when oral iron supplements are not effective. This helps your body make red blood cells, improving health and energy levels.

37,800 services85 patients

Injection, pembrolizumab, 1 mg J9271

Pembrolizumab is a medication given via injection to help your body's immune system fight certain types of cancer. It's typically administered in a hospital or clinic by a healthcare professional.

25,600 services18 patients

Injection, ferric carboxymaltose, 1 mg J1439

Ferric carboxymaltose is an iron supplement injection. It's given when your body needs more iron than you can consume through diet, like in anemia. The injection is administered by a healthcare professional into a vein.

21,000 services14 patients

Injection, denosumab, 1 mg J0897

Denosumab is a medication given via injection to strengthen your bones. It works by slowing down the cells that break down bone, improving bone density and reducing the risk of fractures. It's often used for osteoporosis treatment.

4,200 services20 patients

Injection, dexamethasone sodium phosphate, 1 mg J1100

Dexamethasone sodium phosphate is a medication given via injection. It is a type of steroid that helps reduce inflammation and immune responses. It can be used to treat a variety of conditions, such as allergies, skin conditions, arthritis, and more.

1,616 services37 patients

Complete blood cell count (red cells, white blood cell, platelets), automated test and automated differential white blood cell count 85025

A Complete Blood Cell Count is a common test that measures various components of the blood, including red cells (carry oxygen), white cells (fight infection), and platelets (help blood clot). An automated test ensures accuracy. The differential count provides detailed information about white cell types.

868 services343 patients

Infusion, normal saline solution, 250 cc J7050

An infusion of normal saline solution, 250 cc, involves administering a sterile saltwater solution into your body through a vein, usually in your arm. This helps to replenish fluids, maintain hydration, and balance electrolytes in your body.

819 services144 patients

Insertion of needle into vein for collection of blood sample 36415

This procedure involves inserting a small needle into a vein, typically in your arm, to collect a blood sample. It's a quick and simple process to help diagnose or monitor health conditions. You may feel a small prick, but discomfort is minimal.

769 services367 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.

700 services254 patients

Injection, palonosetron hcl, 25 mcg J2469

Palonosetron HCL is an injection used to prevent nausea and vomiting caused by chemotherapy. It works by blocking a natural substance (serotonin) in the body that can cause vomiting. This helps improve your comfort during cancer treatment.

620 services23 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.

390 services309 patients

Administration of chemotherapy into vein, 1 hour or less 96413

Chemotherapy is a treatment that uses drugs to destroy cancer cells. When administered into a vein, it's often through an IV. This procedure usually lasts 1 hour or less. You may feel a slight pinch as the needle is inserted, but it's generally painless.

330 services59 patients

Blood test, basic group of blood chemicals (calcium, ionized) 80047

A basic group of blood chemicals test, including calcium and ionized, is a simple procedure where a small amount of blood is drawn from your arm. This test helps assess your body's overall health and detect potential disorders like kidney disease or bone disease.

328 services90 patients

Injection of additional new drug or substance into vein 96375

This procedure involves introducing a new medication or substance into your bloodstream via a vein. It's typically done using a small needle. The substance can help treat various conditions or assist in diagnostic procedures. It's generally safe and monitored by professionals.

261 services44 patients

Infusion into a vein for therapy, prevention, or diagnosis, 1 hour or less 96365

This is a procedure where a medical professional inserts a small tube into your vein to deliver medication, nutrients, or fluids directly into your bloodstream. This can be for treatment, prevention, or diagnosis. The process typically takes less than an hour.

231 services106 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.

160 services40 patients

Infusion into a vein for therapy, prevention, or diagnosis, additional sequential infusion, 1 hour or less 96367

This procedure involves injecting fluids or medication directly into your vein. It's used for treatment, prevention, or diagnosis. An additional sequential infusion may be given within an hour if needed. This helps to ensure the medicine is distributed effectively in your body.

151 services39 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.

126 services84 patients

New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more 99204

This is a first-time office or outpatient visit lasting between 45-59 minutes. The healthcare provider evaluates your health, discusses your medical history, and may suggest further tests or treatments. It's an opportunity to ask questions and understand your health better.

80 services80 patients

Administration of additional new drug or substance into vein, 1 hour or less 96417

This procedure involves introducing a new drug or substance into your vein, typically via an IV drip. It lasts for an hour or less. This method allows the substance to quickly reach your bloodstream, ensuring rapid and effective treatment.

75 services20 patients

Administration of chemotherapy into vein, each additional hour 96415

Chemotherapy is a treatment method that uses drugs to destroy cancer cells. The drugs are administered into a vein, usually in the arm. Each additional hour of chemotherapy allows for more of the medication to enter your bloodstream to fight against the cancer cells.

63 services14 patients

Infusion into a vein for hydration, each additional hour 96361

This procedure involves delivering fluids directly into your vein to keep your body hydrated. It is typically done when oral hydration is insufficient. Each additional hour means more fluid is infused to ensure adequate hydration.

60 services16 patients

Injection, diphenhydramine hcl, up to 50 mg J1200

Diphenhydramine HCL injection is a medicine given to alleviate symptoms of allergies, colds, or hay fever. It can also help with motion sickness and certain symptoms of Parkinson's disease. Up to 50 mg may be administered depending on your condition.

58 services16 patients

Unclassified drugs J3490

Unclassified drugs are medications that don't fit into an existing category or class due to their unique properties or uses. They may be used for various conditions and their effects may differ widely. Always ask your healthcare provider for more information about these drugs.

58 services19 patients

Infusion, normal saline solution , 1000 cc J7030

An infusion of normal saline solution, 1000 cc, is a common medical procedure. It involves introducing a saltwater solution into your bloodstream via an intravenous (IV) line. This helps to hydrate your body, correct electrolyte imbalances, and deliver medications if needed.

56 services24 patients

New patient office or other outpatient visit with a high level of medical decision making, if using time, 60 minutes or more 99205

This is a first-time patient visit where a healthcare professional spends 60-74 minutes with you. It involves a comprehensive evaluation, including your medical history and current health condition. They'll also advise on preventive health measures and formulate a treatment plan if needed.

53 services52 patients

Irrigation of implanted venous access drug delivery device 96523

Irrigation of an implanted venous access drug delivery device is a procedure to clean or unblock the device. This device is implanted under your skin to allow easy, frequent, and long-term access to your veins for medication delivery. The process involves flushing the device with a sterile solution to ensure it works properly.

19 services11 patients

Hospital Affiliations CMS Care Compare 3

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

The University Of Chicago Medical Center

Acute Care Hospitals · Chicago, IL

3/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number140088

Location5841 South MarylandChicago, IL 60637 · Cook County

Emergency services Birthing friendly

Ingalls Memorial Hospital

Acute Care Hospitals · Harvey, IL

2/5 CMS rating

OwnershipPhysician

CMS Certification Number140191

Location1 Ingalls DriveHarvey, IL 60426 · Cook County

Emergency services Birthing friendly

Silver Cross Hospital And Medical Centers

Acute Care Hospitals · New Lenox, IL

4/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number140213

Location1900 Silver Cross BlvdNew Lenox, IL 60451 · Will County

Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 60637 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

$183.39 typical visit price

range $60.08 – $183.39

Typical copayment $45.84 (range $15.02 – $45.84)

Most-billed visit code 99205

Established Patient

$105.70 typical visit price

range $18.97 – $148.12

Typical copayment $26.42 (range $4.74 – $37.03)

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.

75/100

MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program

Scored through an Alternative Payment Model

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.

DR. DON MARTINEZ M.D.

Radiology (Diagnostic Radiology)