Julia Marx, MD
NPI 1316039183 · Family Medicine Physician · Los Altos, CA
Enrolled with Medicare as Practitioner - Family Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Julia Marx, MD is a Family Medicine Physician provider in Los Altos, CA (NPI 1316039183).
Provider details
- NPI number
- 1316039183
- Entity type
- Individual
- Primary specialty
- Family Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Female
- Sole proprietor
- No
- License
- A61863 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
19 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
467 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 182 | $110 |
| Annual Wellness Visit, Includes a Personalized Prevention Plan of Service (pps), Subsequent VisitG0439 | 109 | $157 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 78 | $153 |
| Administration of Influenza Virus VaccineG0008 | 27 | $39 |
| Established Patient Office Or Other Outpatient Visit With High Level of Medical Decision Making, If Using Time, 40 Minutes Or More99215 | 22 | $217 |
| Administration of Pneumococcal VaccineG0009 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 45 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 281 | 75 |
| Losartan Potassium | 98 | 28 |
| Amlodipine Besylate | 84 | 26 |
| Gabapentin | 83 | 24 |
| Levothyroxine Sodium | 76 | 19 |
| Lisinopril | 74 | 22 |
| Rosuvastatin Calcium |
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-09-29
- Last updated
- 2011-12-15
Frequently asked questions
- What is Julia Marx's NPI number?
- Julia Marx's National Provider Identifier (NPI) is 1316039183, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Julia Marx's specialty?
- Julia Marx is listed in the NPPES registry with a primary specialty of Family Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Julia Marx located?
- Julia Marx's practice location on file with NPPES is 370 Distel Cir, Los Altos, CA 94022-1404.
- What is Julia Marx's phone number?
- The practice phone number listed in the NPPES registry for Julia Marx is (209) 603-8524.
- Does Julia Marx accept Medicare?
- Julia Marx is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Julia Marx's NPI active?
- Yes — Julia Marx's NPI (1316039183) is active in the NPPES registry as of the last update on 2011-12-15.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.