DR. JOHN NICHOLAS SIENKO (O.D.) – Optometrist, NPI 1194895524

DR. JOHN NICHOLAS SIENKO (O.D.) is a healthcare provider. based in Wallingford, Connecticut. specializing in Optometrist. They hold the professional credentials O.D.. They hold a License No. 914 (CT). The NPI Number for DR. JOHN NICHOLAS SIENKO (O.D.) is 1194895524

Main info

Male
46 Years Of Experience
Accepts Medicare Assignment
Name
DR. JOHN NICHOLAS SIENKO (O.D.)
NPI
1194895524
Phone
(203) 265-5152
Address
821 N MAIN STREET EXT
Enumeration Date
9 November 2006
Last Update Date
16 March 2010

Doctor Profile

Medical School Name
NEW ENGLAND COLLEGE OF OPTOMETRY
Secondary Phone
2032655152
Graduation Year
1980 (46 years ago)
PAC ID
5991894883
Group Practice PAC ID
5193812733
Professional Enrollment ID
I20100728000295
Data current as of
19 May 2026

Profile Insights

NPPES metrics only — not quality of care.

Methodology
Experience52
Completeness75
Years active:19State licenses:1Digital endpointsOther names

Loading map...

Provider Addresses for DR. JOHN NICHOLAS SIENKO (O.D.)

  • 821, North Main Street Extension, Yalesville, Wallingford, South Central Connecticut Planning Region, Connecticut, 06492, United States

    WALLINGFORD, CT 064922464

    Phone: (203) 265-5152

    Fax: (203) 265-1562

    Mailing address matches the actual address.

NPPES updates history

No NPPES updates recorded for this provider.

Prescription Activity

Loading prescription activity...

Open Payments (CMS)

No Open Payments data available for this provider.

This can happen when there are no reportable CMS Open Payments records.

Medicare Enrollment & Revalidation

Source: CMS public data · Not endorsed by CMS ·

Educational use only—not medical, billing, or legal advice.

PECOS enrollment status

Participating (accepts Medicare assignment)

Enrollment effective: 2010-07-28

PECOS data refreshed: 2026-05-27

Medicare revalidation (CMS due date list)

Due date not assigned yet

CMS is tracking this Medicare enrollment for revalidation, but has not published a due date.

Enrollment records

1

Earliest due date

Not assigned (TBD)

CMS data updated

2026-06-01

Revalidation progress

  1. Medicare enrolled
  2. On CMS revalidation list
  3. Due date assigned
  4. Revalidate in PECOS

CMS enrollment records

Enrollment IDTypeSpecialtyStateDue date
I20100728000295IOptometryCTTBD

What to do next

  • No action required while the due date shows TBD.
  • Check the CMS Revalidation Lookup Tool periodically — CMS updates the list about every 60 days.
  • Do not submit a revalidation application in PECOS until CMS publishes a concrete due date.

Verify on CMS Revalidation Lookup Tool

Prepare CMS-855 application → · Look up this NPI in PECOS → · Verify on CMS PECOS

Medicare Utilization (FFS)

Source: CMS public data · Not endorsed by CMS · Beneficiary counts under 11 are suppressed in source data ·

Educational use only—not medical, billing, or legal advice.

No Medicare fee-for-service utilization data available for this provider in our database.

Insurance plans in this area (ZIP 06492)

Loading plans...

Provider's Procedures

DR. JOHN NICHOLAS SIENKO (O.D.) performs procedures in Optometrist. See the list of HCPCS codes below.
SpecialtyPractice State
HCPCS Code
Description
Service Count
Beneficiary Count
OPTOMETRYCT92083Measurement of field of vision during daylight conditions2222

Group practice members

Group practice members are other physicians who share the same Group Practice PAC ID with this doctor. When doctors form a group practice and register in PECOS as a single entity, they receive a shared identification number. This table lists all providers in the same group practice.
PAC ID: 5193812733View full group profile
NameSpecialtyState
O P T O M E T R YCT
O P T O M E T R YNY
O P T O M E T R YCT

Reviews

All reviews are moderated before publication. Reviews reflect users' opinions; we do not verify the accuracy of individual reviews.

No reviews yet. Be the first to share your experience — your opinion helps families compare providers.

Frequently asked questions

What is the 10-digit NPI for DR. JOHN NICHOLAS SIENKO (O.D.)?
DR. JOHN NICHOLAS SIENKO (O.D.) — NPI 1194895524 — is the standard way to identify this listing.
Can I rely on DR. JOHN NICHOLAS SIENKO (O.D.) being an active provider?
As of the registry snapshot, DR. JOHN NICHOLAS SIENKO (O.D.) is marked active.
What is DR. JOHN NICHOLAS SIENKO (O.D.)'s specialty?
The listing groups DR. JOHN NICHOLAS SIENKO (O.D.) with Optometrist. Clinical services aligned with this taxonomy classification.
Does DR. JOHN NICHOLAS SIENKO (O.D.) list a practice location?
Patients near Wallingford, Connecticut may find DR. JOHN NICHOLAS SIENKO (O.D.) in results; validate coverage separately.
Why does DR. JOHN NICHOLAS SIENKO (O.D.) have multiple addresses?
2 practice locations appear in the available data. Multiple addresses are common for hospital privileges, telehealth, or multi-site groups.

Similar Providers

930 N COLONY RD STE I
NPI: 1558315275
87 Grandview Ave
NPI: 1366554081
821, North Main Street Extension, Yalesville, Wallingford, South Central Connecticut Planning Region, Connecticut, 06492, United States
NPI: 1922170224
582, North Main Street, Wallingford, South Central Connecticut Planning Region, Connecticut, 06492, United States
NPI: 1114087855
930 N COLONY RD
NPI: 1164567921
North Colony Road, Tracy, Wallingford, New Haven County, Connecticut, 06492, United States
NPI: 1003022377
821, North Main Street Extension, Yalesville, Wallingford, South Central Connecticut Planning Region, Connecticut, 06492, United States
NPI: 1053521419
147 Post Rd E
NPI: 1396920666
60, Church Street, Yalesville, Wallingford, New Haven County, Connecticut, 06492, United States
NPI: 1851565618