Glossary
Tax ID (TIN)
The tax identification number under which a provider or group bills, linking the rendering provider to the correct billing entity during enrollment.
A Tax ID, or Taxpayer Identification Number, is the federal number a provider or organization uses to bill payers and report income, often an EIN for a group or an SSN for a sole practitioner. During payer enrollment, each rendering provider must be associated with the correct billing TIN so that claims and reimbursement flow to the right entity. The TIN is commonly paired with a group's Type 2 NPI, and a mismatch between the two is a frequent cause of claim denials.