Individual provider

Mallory Groff

Psychiatric/Mental Health Nurse Practitioner Registered Nurse Medicare enrolled

Mallory Groff is a Psychiatric/Mental Health Nurse Practitioner in Hockessin, DE, registered under NPI 1255961959. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty.

Getting there

The practice address on file is 724 YORKLYN RD STE 250, Hockessin, DE 19707. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.

724 YORKLYN RD STE 250, Hockessin, DE 19707 Open in Google Maps →

Credentials and Medicare

State licence
LicenceStateSpecialty
828441 NV Psychiatric/Mental Health Nurse…
9426584 FL Registered Nurse
161921 AK Psychiatric/Mental Health Nurse…
R48854 ND Psychiatric/Mental Health Nurse… primary
7531 MN Psychiatric/Mental Health Nurse…

Licences are recorded in 5 states: NV, FL, AK, ND, MN. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.

Medicare (PECOS)
Status
Approved
Provider type
Practitioner - Nurse Practitioner
PAC ID
4688003551

Enrolled in Medicare 3 times, across 3 states:

StateEnrollment IDProvider type
Minnesota I20200803000669 Practitioner - Nurse Practitioner
Delaware I20240110005040 Practitioner - Nurse Practitioner
District of Columbia I20251229000213 Practitioner - Nurse Practitioner

Medicare enrolment is recorded as approved under the provider type Practitioner - Nurse Practitioner. There are 3 separate enrolment records across 3 states (MN, DE, DC). Multiple enrolments usually mean the provider bills Medicare from more than one practice location, or has kept an earlier enrolment after moving. Each record carries its own enrolment ID, listed above. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.

Licensed in 5 states

This provider holds licences in 5 states: Alaska, Florida, Minnesota, North Dakota and Nevada. Multi-state licensure often means the provider works near a state border, covers more than one office, or delivers care by telehealth. If the address above is far from you, it is worth calling to ask whether they practise closer to where you live.

AK Alaska
Licence
161921
Specialty
Psychiatric/Mental Health Nurse…
Verify with the AK board →
FL Florida
Licence
9426584
Specialty
Registered Nurse
Verify with the FL board →
MN Minnesota
Licence
7531
Specialty
Psychiatric/Mental Health Nurse…
Verify with the MN board →
ND North Dakota
Licence
R48854
Specialty
Psychiatric/Mental Health Nurse…
Verify with the ND board →
NV Nevada
Licence
828441
Specialty
Psychiatric/Mental Health Nurse…
Verify with the NV board →

Licence numbers are self-reported to NPPES at registration. They do not confirm a licence is currently active, in good standing, or valid for the specialty shown — only the state board can tell you that, which is why we link to each one.

What Psychiatric/Mental Health covers

Definition to come... NUCC Health Care Provider Taxonomy, code 363LP0808X
Physician Assistants & Advanced Practice Nursing Providers Nurse Practitioner Psychiatric/Mental Health

All registered taxonomy codes

This provider registers 5 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.

CodeSpecialtyLicenceState
363LP0808X Psychiatric/Mental Health Nurse Practitioner Psychiatric/Mental Health 828441 NV
163W00000X Registered Nurse 9426584 FL
363LP0808X Psychiatric/Mental Health Nurse Practitioner Psychiatric/Mental Health 161921 AK
363LP0808X Psychiatric/Mental Health Nurse Practitioner Psychiatric/Mental Health R48854 ND primary
363LP0808X Psychiatric/Mental Health Nurse Practitioner Psychiatric/Mental Health 7531 MN

The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.

Full NPPES record

An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.

NPI1255961959 valid check digit
Entity typeIndividual (NPI-1)
Enumeration dateJan 22, 2020
Last updatedJul 25, 2026
StatusActive
Sole proprietorNo
GenderFemale
Practice address 724 YORKLYN RD STE 250
Hockessin, DE 19707
(302) 215-2228
Fax (302) 208-4943
Other names Mallory Hodgkinson Former Legal Business Name
This record was updated on Jul 25, 2026, which is recent enough that the contact details are likely still accurate.

Number check

1255961959 passes the NPI check digit test The final digit 9 matches the value computed from the first nine digits, so this is a well-formed NPI.
How the check works, step by step

Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.

Digit 8 0 8 4 0 1 2 5 5 9 6 1 9 5
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 2 1 5 9 6 2 9 1

Sum = 61 · next multiple of 10 = 70 · check digit = 9 · actual last digit = 9

A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.

Common questions

What is NPI number 1255961959?
NPI 1255961959 is the National Provider Identifier assigned to Mallory Groff in Hockessin, DE. It is a 10-digit number issued by the Centers for Medicare & Medicaid Services and used on claims, referrals, and prescriptions to identify the provider.
What does Psychiatric/Mental Health cover?
Definition to come...
How do I contact Mallory Groff?
The phone number on file with NPPES is (302) 215-2228, last updated Jul 25, 2026. Because NPPES is only updated when a provider files a change, call ahead to confirm the number and the current practice address before visiting.
Does Mallory Groff accept Medicare?
This NPI has an approved Medicare enrolment in PECOS, which means the provider is enrolled to bill Medicare. Enrolment does not guarantee they are accepting new Medicare patients — verify directly with the office.
Is NPI 1255961959 a valid number?
Yes. 1255961959 passes the Luhn check digit validation that CMS uses for NPI numbers, and it resolves to an active record in the registry.
How to use this page. Everything here comes from public federal records. Tips Health does not verify quality of care, confirm that a licence is currently active, or check malpractice history, and accepts no fees for placement. A listing is not a recommendation. Verify independently before seeking care.