EIN vs TIN: What's the Difference? (2026)

The IRS processes over 250 million tax returns per year, each requiring a TIN. TIN stands for Taxpayer Identification Number. The IRS created this umbrella term to refer to any number they use to identify taxpayers, whether those taxpayers are individuals or businesses. The IRS recognizes five types of TINs: EIN (Employer Identification Number) for business entities, SSN (Social Security Number) for US citizens and authorized workers, ITIN (Individual Taxpayer Identification Number) for individuals who cannot get an SSN, ATIN (Adoption Taxpayer Identification Number) for children in the adoption process, and PTIN (Preparer Tax Identification Number) for tax return preparers.

Why the TIN System Exists

The IRS needs a consistent way to track tax obligations across millions of filers. The TIN system provides this by assigning a unique 9-digit number to every entity and individual that interacts with the US tax system. Each type of TIN has its own format, application process, and issuing authority, but they all serve the same fundamental purpose: identifying who owes what taxes and who has filed what returns. In 2024 alone, the IRS matched 3.2 billion information returns (W-2s, 1099s) to TINs for compliance enforcement.

TIN Usage in Daily Business

In practice, you will rarely hear anyone say "TIN" in conversation. Business owners say "EIN" or "Tax ID." Individuals say "Social Security Number." The term TIN appears mainly on IRS forms, official instructions, and in tax professional conversations. The W-9 form alone uses the term "TIN" 14 times. Understanding that TIN is the parent category helps you navigate forms that use this formal terminology.

TIN Mismatch Penalties

Using the wrong type of TIN on a form triggers IRS notices. The IRS sends approximately 4.5 million CP2100 and B-notices per year for TIN mismatches. A TIN mismatch on a 1099 form results in backup withholding at 24% of payments until corrected. Businesses that receive a B-notice must solicit a corrected TIN within 30 days or face a $310 penalty per form for 2024 filings.

Non-Resident TIN Options

Over 420,000 foreign-owned LLCs operate in the US, each requiring an EIN as their business TIN. Non-US residents who form a US business entity need an EIN, which serves as their business TIN. The process does not require an SSN or ITIN. You file Form SS-4 by fax with the IRS, and they assign an EIN within 7 to 14 business days. This EIN becomes your business's TIN for all US tax and business purposes.

If you also need a personal TIN for US tax filing (for example, to report personal income from your US business), you apply separately for an ITIN using Form W-7. The EIN and ITIN are independent applications. You can get an EIN without having an ITIN, and you do not need the ITIN to apply for the EIN. Most non-residents start with the EIN because it is required to open a bank account and begin operations.

ein.so handles the EIN application for non-residents. We prepare your Form SS-4, fax it to the IRS, and deliver your EIN to your WhatsApp or email. Standard processing costs $49 (14 business days) and Express costs $97 (7 business days). No SSN, no ITIN, no US address required.