Doctor profile · Federal record

Dr. Ronald Mason, MD

Gastroenterology Physician (CMS: Gastroenterology) · Kirkland, WA

  • NPI 1124088430
  • Accepts Medicare
  • MIPS 80.0 / 100 · 2023
  • 40 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
11800 Ne 128Th St, Suite 100
Kirkland, WA 980347201
(425) 899-4500
fax (425) 899-4510
Mailing address
Po Box 34888
Seattle, WA 981241888

Credentials & registration

NPPES · NUCC
NPI registered
March 2006 — 20 yrs on file
Profile last updated
March 25, 2014
Year of graduation
1986 — 40 yrs since
Specialty taxonomy
207RG0100X — NUCC code
State license (1)
Washington #MD00042393
Medicaid
WA #1003010

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1124088430. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
422
Distinct HCPCS
10
Medicare allowed
$61,332
HCPCS Description Services Patients Avg allowed
45380 Biopsy of large bowel using a flexible endoscope 91 91 $154
99214 Established patient office or other outpatient visit, 30-39 minutes 59 53 $141
99213 Established patient office or other outpatient visit, 20-29 minutes 53 45 $100
43239 Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 48 47 $112
99204 New patient office or other outpatient visit, 45-59 minutes 43 43 $182
99232 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 34 24 $84
45385 Removal of polyps or growths of large bowel using an endoscope with mechanical snare 33 33 $268
99222 Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 19 19 $138
99203 New patient office or other outpatient visit, 30-44 minutes 15 15 $124
G0105 Colorectal cancer screening; colonoscopy on individual at high risk 14 14 $188

In context: peer comparison

Among 2 peers in this city , average services per provider: 53. This provider delivers 8.0× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$773
Transactions
31
Manufacturers
11
Payer (manufacturer) Industry Txns Amount
ABBVIE INC. 5 $145.73
PFIZER INC. 7 $131.45
Regeneron Healthcare Solutions, Inc. 4 $121.65
Salix Pharmaceuticals, a division of Bausch Health US, LLC 3 $70.37
Celltrion USA Inc. 2 $58.50
AIMMUNE THERAPEUTICS, INC. 2 $56.09
Celgene Corporation 2 $48.96
Lilly USA, LLC 2 $48.22
GENZYME CORPORATION 2 $47.33
Organon Llc 1 $25.89
Takeda Pharmaceuticals U.S.A., Inc. 1 $18.75

By nature of payment

Food and Beverage
$743
Education
$30

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
784
Patients
217
Total drug cost
$38,963
Drug Type Claims Patients Total cost
Pantoprazole Sodium Generic 376 97 $5,815
Omeprazole Generic 134 30 $1,762
Sod Sulf-Potass Sulf-Mag Sulf (Sodium, Potassium,mag Sulfates) Brand 62 61 $4,785
Famotidine Generic 48 15 $694
Mesalamine Generic 27 0 $16,404
Colesevelam Hcl Generic 22 0 $2,984
Amitriptyline Hcl Generic 21 0 $175
Dexlansoprazole Dr (Dexlansoprazole) Brand 17 0 $4,025
Ursodiol Generic 17 0 $1,444
Furosemide Generic 16 0 $53

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. Ronald Mason's medical specialty?
Dr. Ronald Mason practices Gastroenterology Physician in Kirkland, WA.
Where does Dr. Ronald Mason practice?
Dr. Ronald Mason practices at 11800 Ne 128Th St, Kirkland, WA 980347201. Office phone: 4258994500.
What is Dr. Ronald Mason's NPI?
Dr. Ronald Mason's National Provider Identifier (NPI) is 1124088430, issued by NPPES.
Does Dr. Ronald Mason accept Medicare assignment?
Yes. Dr. Ronald Mason accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Ronald Mason commonly perform?
Top Medicare-reported procedures in 2023: Biopsy of large bowel using a flexible endoscope (HCPCS 45380); Established patient office or other outpatient visit (HCPCS 99214); Established patient office or other outpatient visit (HCPCS 99213). Source: CMS Medicare Physician & Other Practitioners file.