Doctor profile · Federal record

Dr. William Chapin, MD

Endocrinology, Diabetes & Metabolism Physician (CMS: Endocrinology) · Family Medicine Physician · Portland, OR

  • NPI 1083653679
  • Accepts Medicare
  • MIPS 87.8 / 100 · 2023
  • 28 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
10101 Se Main St, Suite 1001
Portland, OR 972162455
(503) 255-3404
Mailing address
Po Box 92900
Portland, OR 972920900

Credentials & registration

NPPES · NUCC
NPI registered
June 2006 — 20 yrs on file
Profile last updated
December 27, 2012
Year of graduation
1998 — 28 yrs since
Specialty taxonomy
207RE0101X — NUCC code
State license (1)
Oregon #MD22016

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1083653679. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
216
Distinct HCPCS
6
Medicare allowed
$24,310
HCPCS Description Services Patients Avg allowed
99204 New patient office or other outpatient visit, 45-59 minutes 73 73 $168
99214 Established patient office or other outpatient visit, 30-39 minutes 59 39 $131
83036 Hemoglobin a1c level 30 18 $10
99213 Established patient office or other outpatient visit, 20-29 minutes 24 23 $91
99451 Telephone, internet, or electronic health record assessment and management with written report by consulting physician, at least 5 minutes 18 18 $36
99203 New patient office or other outpatient visit, 30-44 minutes 12 12 $101

In context: peer comparison

Among 22 peers in this city , average services per provider: 84. This provider delivers 2.6× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$28
Transactions
1
Manufacturers
1
Payer (manufacturer) Industry Txns Amount
Dexcom, Inc. 1 $27.88

By nature of payment

Food and Beverage
$28

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
565
Patients
250
Total drug cost
$154,003
Drug Type Claims Patients Total cost
Levothyroxine Sodium Generic 137 70 $2,656
Alendronate Sodium Generic 58 24 $432
Methimazole Generic 53 26 $770
Jardiance (Empagliflozin) Brand 44 20 $60,368
Metformin Hcl Generic 39 23 $577
Lantus Solostar (Insulin Glargine,hum.Rec.Anlog) Brand 36 23 $30,035
Metformin Hcl Er (Metformin Hcl) Brand 33 21 $665
Synthroid (Levothyroxine Sodium) Brand 28 16 $3,475
Humalog Kwikpen U-100 (Insulin Lispro) Brand 24 12 $17,338
Atorvastatin Calcium Generic 23 0 $256

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. William Chapin's medical specialty?
Dr. William Chapin practices Endocrinology, Diabetes & Metabolism Physician in Portland, OR.
Where does Dr. William Chapin practice?
Dr. William Chapin practices at 10101 Se Main St, Portland, OR 972162455. Office phone: 5032553404.
What is Dr. William Chapin's NPI?
Dr. William Chapin's National Provider Identifier (NPI) is 1083653679, issued by NPPES.
Does Dr. William Chapin accept Medicare assignment?
Yes. Dr. William Chapin accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. William Chapin commonly perform?
Top Medicare-reported procedures in 2023: New patient office or other outpatient visit (HCPCS 99204); Established patient office or other outpatient visit (HCPCS 99214); Hemoglobin a1c level (HCPCS 83036). Source: CMS Medicare Physician & Other Practitioners file.