WILLIAM JAMES DEMARTINI M.D.
NPI 1427091016
Radiology - Diagnostic Radiology in Greenbrae, CA

Q: What is William Demartini's NPI number?

The NPI number for William Demartini is 1427091016. It was assigned to this individual provider in the NPPES registry on June 13, 2006.

Q: What is William Demartini's specialty?

The primary specialty registered for this NPI is Radiology, specializing in Diagnostic Radiology, with taxonomy code 2085R0202X.

Q: When was this NPI record last updated?

The NPPES record for William Demartini was last updated on April 26, 2010. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 16 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.

Active since June 13, 2006PECOS EnrolledAccepts Medicare Assignment

85.65/100

CMS Quality Rating

250 BON AIR RD, GREENBRAE, CA 94904(415) 925-7301 Get Directions Write a Review

NPPES record last updated: April 26, 2010. Verified against the NPPES registry weekly; last sync: October 25, 2026.

On this page

About William James Demartini M.d. NPPES

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

WILLIAM JAMES DEMARTINI M.D. (NPI 1427091016) is an individual diagnostic radiology provider in Greenbrae, California, licensed in California (G27905) and active in the NPI registry since June 2006. He is enrolled in Medicare PECOS and is a graduate of Other (1973).

NPPES Registry Identity

NPI1427091016

Entity TypeIndividualMale

Primary Taxonomy2085R0202X

Provider Legal NameWILLIAM JAMES DEMARTINICredential: M.D.

Location Address250 BON AIR RDGreenbrae, CA 94904-1702

Mailing AddressPo Box 6102Novato, CA 94948-6102 · (415) 884-3418 · Fax (415) 883-8082

Phone(415) 925-7301

Sole ProprietorNo

Medical School CMSOtherGraduated 1973

Enumeration DateJune 13, 2006

Last NPPES UpdateApril 26, 2010

✔ NPI 1427091016 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyRadiology · Diagnostic RadiologyAllopathic & Osteopathic Physicians

Taxonomy Code2085R0202X

License✔ Licensed in CA · G27905

Definition

A radiologist who utilizes x-ray, radionuclides, ultrasound and electromagnetic radiation to diagnose and treat disease.

250 BON AIR RD, Greenbrae, CA 94904

Open in Google Maps ↗

Other Identifiers 14

Medicare PIN00G279058CA

Other300121750CA · Railroad Medicare

Medicare PINBY132YCA

Medicare PIN00G279055CA

Medicare PINBY132WCA

Medicare PIN00G279052CA

Medicare PIN00G279054CA

Medicare PIN00G279059CA

Medicare PIN00G279050CA

Medicare PIN00G279056CA

Medicare PINBY132XCA

Medicare UPINA43540CA

Medicare PIN00G279057CA

Medicaid00G279050CA

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

William James Demartini M.d. 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 ID5799683918

PECOS Enrollment IDI20060209000228

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 William Demartini reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

California Advanced Imaging Medical Associates Inc

13 mi

Diagnostic Radiology

1101 VAN NESS AVE
San Francisco, CA 94109

Reassigned Medicare billing, California enrollment
96 clinicians in this Medicare group

NPI 1881646909 (415) 600-6000

University Of California Sfgh Medical Group

15 mi

Diagnostic Radiology

1001 POTRERO AVENUE BLDG 5, 1ST FL
San Francisco, CA 94110

Reassigned Medicare billing, California enrollment
336 clinicians in this Medicare group

NPI 1063487122 (628) 206-5871

State Of California - Department Of Developmental Services

28 mi

General Acute Care Hospital

15000 ARNOLD DRIVE
Eldridge, CA 95431

Reassigned Medicare billing, California enrollment
69 clinicians in this Medicare group

NPI 1851344220 (707) 938-6000

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 49

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.

Screening 3d breast mammography 77063

Screening 3D breast mammography is a procedure that uses low-dose X-rays to create detailed images of the breast. This allows for early detection of any unusual changes or growths. It's a non-invasive, outpatient procedure that typically takes about 30 minutes.

259 services259 patients

Screening mammography 77067

Screening mammography is a preventative measure that uses low-dose X-rays to take images of the chest area. It's a key tool in early detection of abnormalities, helping to identify issues before they become symptomatic. It is recommended annually for certain age groups.

259 services259 patients

X-ray of chest, 1 view 71045

A chest X-ray, 1 view, is a quick, painless test that produces images of the structures within your chest, such as your heart, lungs, and blood vessels. It helps in diagnosing conditions like pneumonia, heart problems, or lung cancer. You'll stand in front of a machine that emits X-rays, which pass through your body to create the image.

211 services189 patients

Dxa bone density measurement of hip, pelvis, spine 77080

A DXA bone density measurement is a simple, quick, and non-invasive procedure that assesses the strength of your bones. This test uses X-rays to measure the amount of minerals, mainly calcium, in the hip, pelvis, and spine. It helps in early detection of osteoporosis or other bone diseases.

135 services135 patients

X-ray of chest, 2 views 71046

A chest X-ray, 2 views, is a quick, painless test that creates pictures of the structures inside your chest, such as your heart, lungs, and blood vessels. Two different angles are used to get a comprehensive view. This helps in diagnosing conditions like pneumonia, heart problems, or lung cancer.

125 services117 patients

Ct scan head or brain without contrast 70450

A CT scan of the head or brain without contrast is a non-invasive imaging procedure. It uses X-rays to create detailed pictures of your brain, skull, and other structures inside your head. It helps to detect conditions like strokes, tumors, or injuries. No dye (contrast) is used in this test.

113 services109 patients

Ct scan of abdomen and pelvis with contrast 74177

A CT scan of the abdomen and pelvis with contrast is an imaging procedure. A special dye, called contrast, is used to make certain areas more visible. This can help identify issues such as infections, tumors, or other abnormalities. The procedure is painless and usually takes about 30 minutes.

97 services95 patients

X-ray of hip, 2-3 views 73502

An X-ray of the hip with 2-3 views is a non-invasive imaging test. It uses a small amount of radiation to produce pictures of the hip joint. These images help in diagnosing conditions like fractures, arthritis, or other abnormalities. The process is quick and painless.

86 services77 patients

X-ray of shoulder, minimum of 2 views 73030

An X-ray of the shoulder, with a minimum of 2 views, is a non-invasive imaging test. It uses a small amount of radiation to produce images of your shoulder bones. This helps in diagnosing conditions like fractures, arthritis, or other abnormalities. The procedure is quick and painless.

71 services59 patients

X-ray of knee, 4 or more views 73564

An X-ray of the knee, 4 or more views, is a non-invasive imaging test. It involves capturing multiple images of your knee from different angles. This helps in diagnosing conditions such as fractures, arthritis, or infections. The procedure is quick and painless.

61 services50 patients

X-ray of knee, 1-2 views 73560

An X-ray of the knee with 1-2 views is a quick, painless test that produces images of the knee bones. It helps identify fractures, infections, or changes in the knee joint. During the procedure, you'll be asked to stay still while the X-ray machine captures the images.

59 services52 patients

X-ray of lower and sacral spine, 2-3 views 72100

An X-ray of the lower and sacral spine involves capturing images of your lower back area, including the tailbone. This procedure helps in identifying problems like fractures, infections, or deformities. 2-3 different angle views provide a comprehensive picture.

50 services50 patients

Complete ultrasound scan of abdomen 76700

A complete ultrasound scan of the abdomen is a non-invasive imaging procedure. It uses sound waves to produce images of the organs in your abdomen, such as the liver, gallbladder, spleen, pancreas, and kidneys. It helps in diagnosing, monitoring, and planning treatments.

50 services48 patients

X-ray of knee, 3 views 73562

An X-ray of the knee, 3 views, is a non-invasive imaging test. It uses a small amount of radiation to produce images of the knee from three different angles. This helps medical professionals to diagnose and monitor conditions like arthritis, fractures, or infections. The process is quick and painless.

44 services34 patients

Complete ultrasound scan behind abdominal cavity 76770

A complete ultrasound scan behind the abdominal cavity is a non-invasive imaging procedure. It uses sound waves to create pictures of the structures and organs located at the back of your abdomen. It helps in diagnosing health conditions and monitoring ongoing treatments.

43 services43 patients

Mri scan of lower spinal canal without contrast 72148

An MRI scan of the lower spinal canal without contrast is a non-invasive imaging test. It uses a magnetic field and radio waves to produce detailed images of your lower spine. This helps identify issues like disc problems, tumors, or nerve conditions. No dye is used.

39 services39 patients

Ultrasound of both sides of head and neck blood flow 93880

An ultrasound of the head and neck blood flow is a safe, non-invasive procedure that uses sound waves to create images of blood vessels. It helps detect abnormalities like blockages or clots, ensuring optimal blood flow.

39 services39 patients

Mri scan of brain without contrast 70551

An MRI scan of the brain without contrast is a non-invasive imaging test. It uses a magnetic field and radio waves to create detailed images of your brain. It helps in detecting abnormalities like tumors, stroke, inflammation, or infection.

37 services35 patients

Diagnostic digital breast tomosynthesis, unilateral or bilateral (list separately in addition to 77065 or 77066) G0279

Diagnostic digital breast tomosynthesis is a 3D imaging test that allows doctors to examine your breast tissue layer by layer. It's performed on one or both sides. It helps in detecting abnormalities more accurately. It's often done in addition to other tests.

36 services36 patients

Ct scan of chest without contrast 71250

A CT scan of the chest without contrast is a non-invasive imaging procedure. It uses special X-ray equipment to produce detailed images of your chest area, including your lungs and heart. It can help diagnose conditions such as lung diseases or heart disorders. It doesn't involve any dyes or contrast agents.

35 services35 patients

X-ray of foot, minimum of 3 views 73630

An X-ray of the foot, minimum of 3 views, is a non-invasive imaging test. It uses a small amount of radiation to produce images of the bones and tissues in your foot. This helps to identify fractures, infections, or other abnormalities. Multiple views ensure a comprehensive examination.

32 services29 patients

Ct scan of abdomen and pelvis without contrast 74176

A CT scan of the abdomen and pelvis is a non-invasive medical test. It uses special X-ray equipment to create detailed images of your abdominal and pelvic areas. This helps doctors examine organs, tissues, and vessels. No contrast dye is used in this procedure.

32 services31 patients

Ct scan of heart with evaluation of blood vessel calcium 75571

A CT scan of the heart with evaluation of blood vessel calcium is a non-invasive test that uses X-rays to create detailed images of your heart. It helps in detecting and measuring calcium-containing plaque in the arteries, which can indicate heart disease.

31 services31 patients

Ct scan of blood vessels of neck with contrast 70498

A CT scan of the neck's blood vessels with contrast is a diagnostic procedure. It uses X-rays and a special dye to create detailed images of your neck's blood vessels. This helps doctors detect issues such as blockages or abnormalities.

30 services29 patients

Ct scan of upper spine without contrast 72125

A CT scan of the upper spine without contrast is a non-invasive imaging test that uses X-rays to capture detailed images of your neck and upper back. It helps in identifying issues like fractures, tumors, or infections. No dye (contrast) is used in this scan.

30 services29 patients

Ct scan of blood vessels of head with contrast 70496

A CT scan of the head's blood vessels with contrast is a diagnostic procedure. A special dye (contrast) is injected into your body to make the blood vessels visible on the scan. This helps identify issues like blockages or abnormalities in your head's blood vessels.

29 services28 patients

Ct scan of chest with contrast 71260

A CT scan of the chest with contrast is an imaging procedure. A special dye (contrast) is used to highlight specific areas in your body, providing clearer pictures of your chest. This helps in diagnosing conditions related to your lungs, heart, and other chest structures.

29 services29 patients

Mri scan of brain before and after contrast 70553

An MRI scan of the brain, both before and after contrast, helps visualize different brain structures. Initially, images are taken without a contrast agent. Then, a safe dye is injected which helps highlight certain areas, providing clearer, more detailed images.

24 services23 patients

Ct scan of blood vessels of chest with contrast 71275

A CT scan of the chest with contrast is a non-invasive imaging test. It uses X-rays and a special dye to get detailed images of your blood vessels in the chest. This helps in diagnosing conditions related to heart and lungs.

24 services24 patients

Limited ultrasound scan of 1 breast 76642

A limited ultrasound scan of one breast is a non-invasive imaging test. It uses sound waves to create pictures of the inside of your breast. It helps identify any unusual growths or changes. It's safe, quick, and typically painless.

24 services24 patients

Ultrasound study of one arm or leg veins with compression and maneuvers 93971

This is a non-invasive procedure using sound waves to visualize veins in an arm or leg. It involves applying gentle pressure and performing certain movements. It helps identify any abnormal blood flow or clots, ensuring vascular health.

24 services23 patients

Mri scan of upper spinal canal without contrast 72141

An MRI scan of the upper spinal canal without contrast is a non-invasive imaging test. It uses a magnetic field and radio waves to create detailed images of your upper spine. This helps doctors identify issues such as injuries, infections or diseases. No dye is used.

21 services20 patients

Ultrasound scan of head and neck soft tissue 76536

An ultrasound scan of the head and neck soft tissue is a non-invasive procedure that uses sound waves to create images of the soft tissues in these areas. It helps identify any abnormalities or issues, such as tumors, cysts, or infections. It's painless and doesn't involve radiation.

21 services21 patients

Diagnostic mammography of 1 breast 77065

Diagnostic mammography of 1 breast is a detailed imaging test that allows doctors to closely examine a specific area in the breast. It's often used when a routine screening reveals an abnormality. This test can help identify any unusual changes or issues.

20 services20 patients

Ct scan of abdomen and pelvis before and after contrast 74178

A CT scan of your abdomen and pelvis with and without contrast helps visualize your internal organs better. Contrast is a special dye that improves the clarity of the images. It's taken orally or injected into your veins before the scan. The process is painless and quick.

19 services19 patients

Diagnostic mammography of both breasts 77066

Diagnostic mammography involves using special imaging technology to capture detailed images of both breasts. This procedure helps in identifying any unusual changes or abnormalities. It's a crucial step in ensuring breast health and early detection of potential issues.

19 services19 patients

X-ray of wrist, minimum of 3 views 73110

An X-ray of the wrist, minimum of 3 views, is a diagnostic procedure that uses radiation to create images of your wrist from different angles. This helps detect fractures, infections, or other abnormalities for accurate diagnosis and treatment planning.

17 services15 patients

X-ray of hand, minimum of 3 views 73130

An X-ray of the hand, minimum of 3 views, is a non-invasive imaging test. It uses a small amount of radiation to produce images of the bones in your hand from different angles. This helps in diagnosing fractures, infections, arthritis, or other abnormalities. It's quick and painless.

17 services14 patients

X-ray of ribs on side of body, minimum of 3 views 71101

This is a diagnostic procedure where a machine emits a small amount of radiation to capture images of your ribs from at least three different angles. It helps to identify issues like fractures or infections. It's a quick, painless process.

16 services16 patients

X-ray of upper spine, 4-5 views 72050

An X-ray of the upper spine with 4-5 views is a non-invasive imaging test. It uses radiation to capture detailed images of the bones and structures in your neck and upper back. This procedure helps identify issues like fractures, infections, or deformities.

15 services15 patients

X-ray of middle spine, 2 views 72070

An X-ray of the middle spine, or thoracic spine, involves capturing two different images of the area. This non-invasive procedure uses small amounts of radiation to visualize the bones and tissues in your back, helping to identify any abnormalities or injuries.

15 services15 patients

Ct scan of lower spine without contrast 72131

A CT scan of the lower spine without contrast is a non-invasive imaging test. It uses X-rays to create detailed images of your lower back area, helping to detect conditions like fractures, infections, or tumors. It's painless and generally quick.

14 services14 patients

Fluoroscopic guidance for needle placement 77002

Fluoroscopic guidance for needle placement is a medical procedure that uses a special X-ray technology to help accurately place a needle in the body. It's often used in biopsies, injections or other treatments to ensure precision and safety.

14 services12 patients

X-ray of ankle, minimum of 3 views 73610

An ankle X-ray is a quick, painless imaging test. It involves capturing at least three different images or 'views' of your ankle using small amounts of radiation. These images help identify any abnormalities or injuries, such as fractures or arthritis.

13 services12 patients

Low dose ct scan of chest for lung cancer screening 71271

A low-dose CT scan of the chest is a quick, painless procedure that uses a small amount of radiation to create detailed images of your lungs. It's a key tool for early detection of lung cancer, especially for those at high risk.

12 services12 patients

Ultrasound scan of uterus, ovaries, tubes, cervix and pelvic area through vagina 76830

An ultrasound scan of the lower abdominal region is a safe, non-invasive procedure that uses sound waves to create images of internal structures. This helps in checking the health of reproductive organs and detecting any abnormalities. The scan is done via a small probe inserted into the body.

12 services12 patients

Complete ultrasound scan of pelvis 76856

A complete ultrasound scan of the pelvis is a safe, non-invasive imaging procedure. It uses sound waves to create pictures of your lower abdomen area, helping doctors to evaluate and diagnose any potential issues. It's painless and usually takes about 30 minutes.

12 services12 patients

Limited ultrasound scan of joint or other extremity structure except blood vessels 76882

A limited ultrasound scan of a joint or other extremity structure lacking blood vessels is a non-invasive procedure that uses sound waves to create images of the inside of your body. This helps in diagnosing and monitoring conditions related to your joints or other similar structures.

11 services11 patients

Dxa bone density measurement of forearm, finger, hand, or foot 77081

A DXA bone density measurement of the forearm, finger, hand, or foot is a non-invasive procedure that uses X-rays to measure the amount of calcium and other minerals in your bones. This test helps to assess the strength of your bones and your risk of fractures.

11 services11 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94904 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

$104.67 typical visit price

range $69.07 – $202.63

Typical copayment $26.16 (range $17.26 – $50.65)

Most-billed visit code 99203

Established Patient

$85.00 typical visit price

range $23.44 – $166.64

Typical copayment $21.25 (range $5.86 – $41.66)

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.

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.

85.65/100

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

Scored as part of a group practice

Quality

88.33

Improvement Activities

Cost

69.53

Reported Quality Measures

Radiation Consideration for Adult CT: Utilization of Dose Lowering Techniques

Percentage of final reports for patients aged 18 years and older undergoing CT with documentation that one or more of the following dose reduction techniques were used: - Automated exposure control - Adjustment of the mA and/or kV according to patient size -…

100%162 patients

Radiology: Reminder System for Screening Mammograms

Percentage of patients undergoing a screening mammogram whose information is entered into a reminder system with a target due date for the next mammogram

100%89 patients

Providers report different measures because they deliver different services; reporting more or less information is not a reflection of quality. Star ratings appear only where CMS assigned them.

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.

MESKEREM DABA RN, BSN

Registered Nurse (Psychiatric/Mental Health)

250 BON AIR RD
GREENBRAE, CA 94904

Marin County (415) 473-6666

ALEC CHANG D.O.

Psychiatry & Neurology (Psychiatry)

250 BON AIR RD
GREENBRAE, CA 94904

Marin County (415) 473-6835

MARIN HOSPITALIST MEDICAL GROUP, INC.

Internal Medicine

250 BON AIR RD, 3RD FLOOR
GREENBRAE, CA 94904

Marin County (415) 925-7545

DR. STEPHEN C ALLISON M.D.

Psychiatry & Neurology (Psychiatry)

250 BON AIR RD
GREENBRAE, CA 94904

Marin County (415) 925-7663

ANNIE LINN STODDARD

Rehabilitation Practitioner

250 BON AIR RD
GREENBRAE, CA 94904

Marin County (415) 473-6835

SARENA NAPIER ASW

Counselor (Mental Health)

250 BON AIR RD
GREENBRAE, CA 94904

Marin County (415) 473-6619

JULIET LIANNE HUNTINGTON CNM

Advanced Practice Midwife

250 BON AIR RD
GREENBRAE, CA 94904

Marin County (415) 925-7010

ZAMBIA RICHEA PLAYER RN

Registered Nurse

250 BON AIR RD
GREENBRAE, CA 94904

Marin County (415) 473-6666

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 William Demartini's NPI number?

The NPI number for William Demartini is 1427091016. It was assigned to this individual provider in the NPPES registry on June 13, 2006.

Where is William Demartini located?

William Demartini practices at 250 Bon Air Rd, Greenbrae, CA 94904. The listed phone number is (415) 925-7301.

What is William Demartini's specialty?

The primary specialty registered for this NPI is Radiology, specializing in Diagnostic Radiology, with taxonomy code 2085R0202X.

Is William Demartini enrolled in Medicare?

Yes. William Demartini 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 organizations bill Medicare for William Demartini's services?

According to the CMS Revalidation Reassignment List (October 2026 release), William Demartini reassigns Medicare benefits to 3 organizations: California Advanced Imaging Medical Associates Inc (San Francisco, CA), University Of California Sfgh Medical Group (San Francisco, CA) and State Of California - Department Of Developmental Services (Eldridge, CA). 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 William Demartini'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 William Demartini was last updated on April 26, 2010. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 16 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.