Darwin Tsang, O.D.
NPI 1619344918 · Optometrist · Petaluma, CA
Enrolled with Medicare as Practitioner - Optometry · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Darwin Tsang, O.D. is a Optometrist provider in Petaluma, CA (NPI 1619344918).
Provider details
- NPI number
- 1619344918
- Entity type
- Individual
- Primary specialty
- OptometristEye and Vision Services Providers
- Credential
- O.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- 15225 TLG (CA)
Specialties & taxonomies
Eye and Vision Services Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
10 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
260 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) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 92 | $154 |
| Photography of the Retina92250 | 67 | $47 |
| New Patient Office Or Other Outpatient Visit With Moderate Level of Medical Decision Making, If Using Time, 45 Minutes Or More99204 | 54 | $163 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 34 | $88 |
| Established Patient Office Or Other Outpatient Visit With Straightforward Medical Decision Making, If Using Time, 10 Minutes Or More99212 | 13 | $69 |
Typical Medicare-allowed amounts for these services range $47–$163 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$189 across 7 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
Registry dates
- Enumerated
- 2015-08-21
- Last updated
- 2016-09-23
Frequently asked questions
- What is Darwin Tsang's NPI number?
- Darwin Tsang's National Provider Identifier (NPI) is 1619344918, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Darwin Tsang's specialty?
- Darwin Tsang is listed in the NPPES registry with a primary specialty of Optometrist (Eye and Vision Services Providers).
- Where is Darwin Tsang located?
- Darwin Tsang's practice location on file with NPPES is 401 Kenilworth Dr, Petaluma, CA 94952-3400.
- What is Darwin Tsang's phone number?
- The practice phone number listed in the NPPES registry for Darwin Tsang is (707) 775-6022.
- Does Darwin Tsang accept Medicare?
- Darwin Tsang is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Darwin Tsang's NPI active?
- Yes — Darwin Tsang's NPI (1619344918) is active in the NPPES registry as of the last update on 2016-09-23.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.