NPI Portal NPI Lookup & Verification

Robert Michael Stack, MD

Robert Michael Stack is a Orthopaedic Surgery Physician provider (Orthopaedic Surgery) practicing in Las Cruces, NM, registered in the NPPES registry with NPI 1134111461 since 2005. The credential MD stands for Doctor of Medicine. Practices at Las Cruces Orthopaedic Associates, PC (listed at the same practice address in NPPES).

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NPI 1134111461
Entity type Individual (Type 1)
Name Robert Michael Stack
Credential MD
Sex Male
Practice address 675 AVENIDA DE MESILLA, Las Cruces, NM, 88005
Phone 5055253535
Fax 5055270217
Enumeration date 2005-08-23
Last updated in NPPES 2007-10-29

Taxonomy & licenses

Taxonomy code Specialty Primary License State
207X00000X Orthopaedic Surgery Physician Primary 78268 NM

MD — Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
26210 Other NM PRESBYTERIAN
16010 Other NM HMO
2666 Other NM BC BS
0761430001 Other NM DMERC
39445593 Other NM CHAMPUS
88005C005 Other NM TRICARE
Copy-ready billing details
Provider: Robert Stack, MD
NPI: 1134111461
Taxonomy: 207X00000X (Orthopaedic Surgery Physician)
Address: 675 AVENIDA DE MESILLA, Las Cruces, NM, 88005

Other providers at this practice address

NPI Name Type Specialty Location
1144212473 Las Cruces Orthopaedic Associates, PC Organization Orthopaedic Surgery Physician Las Cruces, NM
1811978919 Wayne Lindsey Individual Orthopaedic Surgery Physician Las Cruces, NM
1124076948 Paul Saiz Individual Orthopaedic Surgery Physician Las Cruces, NM
1104126481 Michael Hamrick Individual Nurse Practitioner Las Cruces, NM

Verify this record

Cross-check NPI 1134111461 against the authoritative CMS record: view Robert Michael Stack on the official NPPES registry .

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes — even if the provider moves or changes specialty. Read the full guide or validate an NPI number.

Frequently asked questions

Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.
What specialty is Robert Stack?
Robert Stack is registered in NPPES with the primary taxonomy of Orthopaedic Surgery Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2007-10-29.