Doctor profile · Federal record

Dr. William Johnston, M.D.

Emergency Medicine Physician (CMS: Emergency Medicine) · Palo Alto, CA

  • NPI 1417366584
  • Accepts Medicare
  • MIPS 86.3 / 100 · 2023
  • 13 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

Operates at 4 locations .

NPPES Updated May 11, 2026
Primary practice
3801 Miranda Ave
Palo Alto, CA 943041207
(650) 493-5000
Additional location
1200 El Camino Real
South San Francisco, CA 940803208
(650) 742-2000
Additional location
222 W 39Th Ave
San Mateo, CA 944034364
(650) 573-2222
Show 1 more location
Additional location
30 Prospect Ave
Hackensack, NJ 076011914
(551) 996-2000
Mailing address
2015 Ray Dr
Burlingame, CA 940104655

Credentials & registration

NPPES · NUCC
NPI registered
August 2014 — 12 yrs on file
Profile last updated
August 12, 2021
Year of graduation
2013 — 13 yrs since
Specialty taxonomy
207P00000X — NUCC code
State license (1)
California #A138944

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1417366584. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
28
Distinct HCPCS
2
Medicare allowed
$4,404
HCPCS Description Services Patients Avg allowed
99284 Emergency department visit with moderate level of medical decision making 15 15 $130
99285 Emergency department visit with high level of medical decision making 13 13 $189

In context: peer comparison

Among 7 peers in Palo Alto Emergency Medicine Physician, average services per provider: 34. This provider delivers 0.8× the peer median.

Frequently asked questions

Auto-generated from federal data
What is Dr. William Johnston's medical specialty?
Dr. William Johnston practices Emergency Medicine Physician in Palo Alto, CA.
Where does Dr. William Johnston practice?
Dr. William Johnston practices at 3801 Miranda Ave, Palo Alto, CA 943041207. Office phone: 6504935000.
What is Dr. William Johnston's NPI?
Dr. William Johnston's National Provider Identifier (NPI) is 1417366584, issued by NPPES.
Does Dr. William Johnston accept Medicare assignment?
Yes. Dr. William Johnston accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. William Johnston commonly perform?
Top Medicare-reported procedures in 2023: Emergency department visit with moderate level of medical decision making (HCPCS 99284); Emergency department visit with high level of medical decision making (HCPCS 99285). Source: CMS Medicare Physician & Other Practitioners file.