Mark William Onaitis, MD
Thoracic Surgery (Cardiothoracic Vascular Surgery) Physician · San Diego, CA
Mark William Onaitis, MD is a thoracic surgery (cardiothoracic vascular surgery) physician with a practice address in San Diego, California, and NPI 1841310638, issued on Mar 29, 2007. Check the license (California A144886, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Mark William Onaitis
- Credential
- MD
- Primary taxonomy
- Thoracic Surgery (Cardiothoracic Vascular Surgery) Physician 208G00000X
- License number
- A144886 CA
Self-reported in NPPES; status is on the state search - Practice location
- 200 W Arbor Dr, San Diego, CA 92103
- Phone
- (858) 657-7777
- Enumerated
- Mar 29, 2007
- Record last updated
- Feb 21, 2019 (not updated in 7 years: call before relying on the address or phone)
- Fax
- (858) 657-5058
- Medicare enrollment
- Enrolled (PECOS I20161025002233); accepts Medicare assignment
- Medical or professional school
- Duke University School Of Medicine, 1997
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest thoracic surgery (cardiothoracic vascular surgery) physician records → All 634 in California → Look up another NPI →
Also registered at 200 W Arbor Dr
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Alison A'Court, MDAnesthesiology Physician1912218199
- Benjamin Abbadessa, M.D.Colon & Rectal Surgery Physician1255593612
- Geraldine Abcede, RNCertified Registered Nurse Anesthetist1982384046
- Joseph Abdelmalek, M.DNephrology Physician1740485531
- Kristy AbelCertified Registered Nurse Anesthetist1962113035
- Paula Abeleda, NPFamily Nurse Practitioner1558945022
Verify Mark William Onaitis in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A144886Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
62% fewer Medicare Part D claims than the average thoracic surgery (cardiothoracic vascular surgery) physician in 2024
38 Medicare Part D claims for 26 beneficiaries, against an average of 101 among the 2,587 providers of this specialty who prescribed in Part D. Brand-name drugs were 0% of claims.
Most prescribed
- Gabapentin21 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Industry payments in 2024: $36,281.33
19 payments; by number, the most common kind was food and beverage; the largest payer was Intuitive Surgical, Inc. The 4,047 providers of this specialty with any payment received $7,828.84 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Bills Medicare through one group practice
- Regents OF The University OF CaliforniaSan Diego, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Mark William Onaitis among 634 thoracic surgery (cardiothoracic vascular surgery) physician records in California
Mark William Onaitis, MD is one of 634 thoracic surgery (cardiothoracic vascular surgery) physician records with a practice address in California. 75% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2007, is newer than 55% of them.
- NPI issued2007 · 55% of these records are older, 37% newer
- In a Medicare fileYes · 75% of these records are
- In the CMS Doctors and Clinicians fileYes · 64% of these records are
- Graduated1997 · median 1997 among the 408 with a school on file
- Record last updated2019 · 59% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 208G00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Thoracic Surgery (Cardiothoracic Vascular Surgery) Physician providers in California
There are 634 thoracic surgery (cardiothoracic vascular surgery) physician records in California.
All 634 in California → Every provider in San Diego → Thoracic Surgery (Cardiothoracic Vascular Surgery) Physician nationwide →
The 8 thoracic surgery (cardiothoracic vascular surgery) physician records with the nearest ZIP codes
- Joelle Coletta, M.D.San Diego, CA 921031447222377
- Ian Glenn, M.D.San Diego, CA 921031124381595
- Eugene Golts, M.D.San Diego, CA 921031316000649
- James Hemp, M.D.San Diego, CA 921031124006382
- Jessica Hudson, M.D., M.SC., B.S.San Diego, CA 921031528321650
- Mohammad Islami Manuchehry, MDSan Diego, CA 921031841362241
- Stuart Jamieson, MDSan Diego, CA 921031649203415
- Jolene Kriett, MDSan Diego, CA 921031699707299
Common questions
What is Mark William Onaitis, MD's NPI number?
Mark William Onaitis, MD's National Provider Identifier (NPI) is 1841310638, issued on Mar 29, 2007. An NPI identifies a provider in billing; it is not a license.
Where is Mark William Onaitis, MD located?
The NPPES record lists a practice address at 200 W Arbor Dr, San Diego, CA, 92103. Phone: (858) 657-7777. Providers update this record themselves, so call before visiting.
How can I verify Mark William Onaitis, MD's license?
NPPES lists California license number A144886, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Mark William Onaitis, MD prescribe under Medicare Part D?
In 2024, Mark William Onaitis, MD had 38 Medicare Part D claims for 26 beneficiaries; the average among thoracic surgery (cardiothoracic vascular surgery) physician prescribers was 101. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.