Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum
Ms. Mary Ann Hayes, LCSWC
Social Worker in Bethesda, MD · enumerated 2007.
Data current as of Jul 13, 2026 · sourced from CMS NPPES
National Provider Identifier
1831235332
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Registry record
Entity type Individual (Type 1)
Name Ms. Mary Ann Hayes
Credential LCSWC
Sex Female
Practice address 4401 East West Highway, Suite 200, Bethesda, MD, 20814
Phone (301) 230-5558
Fax (301) 320-4011
Enumeration date Jan 30, 2007
Last updated in NPPES Jul 8, 2007
Taxonomy & licenses
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.
Frequently asked questions
What specialty is Mary Ann Hayes?
Mary Ann Hayes is registered in NPPES with the primary taxonomy of Social Worker. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
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.
Other providers at this practice address
Browse all →Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-08.