Melissa Mao, MD
NPI 1245594498 · Surgical Oncology Physician · Orange, CA
Enrolled with Medicare as Practitioner - General Surgery · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Melissa Mao, MD is a Surgical Oncology Physician provider in Orange, CA (NPI 1245594498).
Provider details
- NPI number
- 1245594498
- Entity type
- Individual
- Primary specialty
- Surgical Oncology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Female
- Sole proprietor
- No
- License
- A167735 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
13 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)25% of score
165 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
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 .
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) |
|---|---|---|
| Telephone Medical Discussion With Physician, 5-10 Minutes99441 | 29 | $55 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 25 | $68 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 23 | $86 |
| New Patient Office Or Other Outpatient Visit With Low Level of Medical Decision Making, If Using Time, 30 Minutes Or More99203 | 15 | $85 |
| New Patient Office Or Other Outpatient Visit With Low Level of Medical Decision Making, If Using Time, 30 Minutes Or More99203 | 15 | $113 |
| New Patient Office Or Other Outpatient Visit With Moderate Level of Medical Decision Making, If Using Time, 45 Minutes Or More |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$262 across 3 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Additional practice locations (1)
- 8815 Germantown Ave Ste 22Philadelphia, PA 19118-2722Phone: (215) 248-8887Fax: (215) 836-5372
Registry dates
- Enumerated
- 2012-07-02
- Last updated
- 2025-06-02
- Certified
- 2025-06-02
Frequently asked questions
- What is Melissa Mao's NPI number?
- Melissa Mao's National Provider Identifier (NPI) is 1245594498, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Melissa Mao's specialty?
- Melissa Mao is listed in the NPPES registry with a primary specialty of Surgical Oncology Physician (Allopathic & Osteopathic Physicians).
- Where is Melissa Mao located?
- Melissa Mao's practice location on file with NPPES is 101 the City Dr S Bldg 23, Orange, CA 92868-3201.
- What is Melissa Mao's phone number?
- The practice phone number listed in the NPPES registry for Melissa Mao is (714) 456-8000.
- Does Melissa Mao accept Medicare?
- Melissa Mao is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Melissa Mao's NPI active?
- Yes — Melissa Mao's NPI (1245594498) is active in the NPPES registry as of the last update on 2025-06-02.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.