Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum
Thomas Wei Guo Bai, MD
Psychiatry Physician in Colton, CA · enumerated 2007.
Data current as of Jul 13, 2026 · sourced from CMS NPPES
National Provider Identifier
1538204359
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Registry record
Entity type Individual (Type 1)
Name Thomas Wei Guo Bai
Credential MD
Sex Male
Practice address 400 N Pepper Ave # Bh, Colton, CA, 92324
Phone (909) 580-3830
Enumeration date Feb 20, 2007
Last updated in NPPES Mar 9, 2012
Taxonomy & licenses
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure.
About the MD credential
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
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 Thomas Bai?
Thomas Bai is registered in NPPES with the primary taxonomy of Psychiatry Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2012-03-09.