William Chang, MD
William Chang, MD is a Critical Care Medicine (Internal Medicine) Physician in Monterey Park, CA, registered under NPI 1003236688. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty.
Getting there
Here is what surrounds this office in Monterey Park, based on OpenStreetMap data collected Sep 13, 2026. Parking is available about 0.35 mi away. The nearest transit stop is 0.35 mi away, served by Metro 70, 770. If you arrive early, there is a coffee shop 0.49 mi away.
Getting here and what is nearby
Transit Spirit 447 ft ~2 min
Parking 651 ft ~3 min
Transit Montebello 679 ft ~3 min
Convenience 76 672 ft ~3 min
Convenience ampm 685 ft ~3 min
Gas station 76 686 ft ~3 min
Gas station Arco 695 ft ~3 min
Restaurant DimSum Express 670 ft ~3 min
326 North Garfield Avenue, Monterey Park 91754
Mo-Su 07:30-19:00
Restaurant Yunnan Restaurant 936 ft ~4 min
301 North Garfield Avenue, Monterey Park 91754
Restaurant Banh Mi Hoa Phat 946 ft ~4 min
301 North Garfield Avenue, Monterey Park 91754
Grocery Hong Kong Supermarket 0.30 mi ~6 min
Parking 0.32 mi ~7 min
Transit Metro 70, 770 0.35 mi ~7 min
Parking 0.35 mi ~7 min
Grocery T.S. Emporium 0.37 mi ~8 min
Convenience Lucky Grass Convenience Store 幸運便利店 0.42 mi ~9 min
331 West Garvey Avenue, Monterey Park 91754
Mo-Su 08:30-23:00
Hotel Lincoln Plaza Hotel 0.42 mi ~9 min
123 South Lincoln Avenue, Monterey Park 91755
Gas station Shell 0.44 mi ~9 min
Grocery USG Supermarket 0.47 mi ~10 min
Coffee JJ Hong Kong Cafe 0.49 mi ~10 min
Distances are straight‑line estimates — walking routes may be longer. Hours and phone numbers can change; call ahead to confirm.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| A140305 | CA | Critical Care Medicine (Internal… primary |
| A140305 | CA | Pulmonary Disease Physician |
This provider holds licence A140305 issued in CA. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
- Status
- Approved
- Provider type
- Practitioner - Critical Care (intensivists)
- PAC ID
- 3476884156
- Enrollment ID
- I20191010000984
Medicare enrolment is recorded as approved under the provider type Practitioner - Critical Care (intensivists). Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What Critical Care Medicine covers
An internist who diagnoses, treats and supports patients with multiple organ dysfunction. This specialist may have administrative responsibilities for intensive care units and may also facilitate and coordinate patient care among the primary physician, the critical care staff and other specialists. NUCC Health Care Provider Taxonomy, code 207RC0200X
All registered taxonomy codes
This provider registers 2 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 207RC0200X | Critical Care Medicine (Internal Medicine) Physician Critical Care Medicine | A140305 | CA | primary |
| 207RP1001X | Pulmonary Disease Physician Pulmonary Disease | A140305 | CA |
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1003236688 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Apr 22, 2014 |
| Last updated | Aug 18, 2021 |
| Status | Active |
| Sole proprietor | No |
| Gender | Male |
| Credential | MD |
| Practice address |
500 N GARFIELD AVE STE 204 Monterey Park, CA 91754 (626) 280-4393 |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 0 | 0 | 3 | 2 | 3 | 6 | 6 | 8 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 0 | 3 | 4 | 3 | 3 | 6 | 7 |
Sum = 52 · next multiple of 10 = 60 · check digit = 8 · actual last digit = 8
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.