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WILLIAM HAYNES
NPI 1831610161
Nurse Practitioner - Psychiatric/Mental Health in Middletown, MD

Active since June 27, 2017PECOS Enrolled
7101 FLINT CT, MIDDLETOWN, MD 21769(240) 675-4393 Get Directions Write a Review

NPPES record last updated: September 2, 2021. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About William Haynes NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

WILLIAM HAYNES (NPI 1831610161) is an individual psychiatric/mental health provider in Middletown, Maryland, licensed in Maryland (R183173) and active in the NPI registry since June 2017. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1831610161
Entity TypeIndividualMale
Primary Taxonomy363LP0808X
Provider Legal NameWILLIAM HAYNES
Location Address7101 FLINT CTMiddletown, MD 21769-7426
Mailing Address7101 Flint CtMiddletown, MD 21769-7426 · (240) 675-4393
Phone(240) 675-4393
Sole ProprietorYes
Enumeration DateJune 27, 2017
Last NPPES UpdateSeptember 2, 2021
NPPES CertifiedSeptember 2, 2021
✔ NPI 1831610161 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyNurse Practitioner · Psychiatric/Mental HealthPhysician Assistants & Advanced Practice Nursing Providers
Taxonomy Code363LP0808X
License✔ Licensed in MD · R183173
7101 FLINT CT, Middletown, MD 21769
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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

William Haynes is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show William Haynes reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Cornerstone Montgomery, Inc.
31 mi
Mental Health (Including Community Mental Health Center)
2 TAFT CT, A
Rockville, MD 20850
  • Reassigned Medicare billing, District of Columbia enrollment
  • 51 clinicians in this Medicare group
NPI 1134591985 (301) 493-4200

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 21769 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$89.75 typical visit price
range $57.99 – $175.57
Typical copayment $22.43 (range $14.49 – $43.89)
Most-billed visit code 99203
Established Patient
$102.11 typical visit price
range $18.66 – $143.02
Typical copayment $25.52 (range $4.66 – $35.75)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is William Haynes's NPI number?

The NPI number for William Haynes is 1831610161. It was assigned to this individual provider in the NPPES registry on June 27, 2017.

Where is William Haynes located?

William Haynes practices at 7101 Flint Ct, Middletown, MD 21769. The listed phone number is (240) 675-4393.

What is William Haynes's specialty?

The primary specialty registered for this NPI is Nurse Practitioner, specializing in Psychiatric/Mental Health, with taxonomy code 363LP0808X.

Is William Haynes enrolled in Medicare?

Yes. William Haynes is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for William Haynes's services?

According to the CMS Revalidation Reassignment List (October 2026 release), William Haynes reassigns Medicare benefits to Cornerstone Montgomery, Inc. (Rockville, MD). The reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for William Haynes's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for William Haynes was last updated on September 2, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 5 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.