EIN
Employer Identification Number — 9-digit IRS-issued tax ID used on Form 5500-EZ.
Definition
An EIN (Employer Identification Number) is the 9-digit federal tax ID assigned by the IRS to a business entity. The plan sponsor's EIN appears on Form 5500-EZ line 2b. Sole proprietors who use their SSN for business taxes must still obtain an EIN to file Form 5500-EZ.
Why it matters
For IRS Form 5500-EZ, this term helps decide which records, dates, values, or review questions belong in the packet.
How the tool uses it
Solo 5500 treats this as a review signal. The user enters the facts, checks the source-linked explanation, reviews the packet, and files through the official channel when the supported case still fits.
When to check the source
Check the official source when the answer depends on eligibility, late filing relief, official correspondence, valuation, or a fact you cannot verify from your own records.
Source and review date
Last reviewed: . Use the linked source for the official wording behind this term.
Official source: IRS Form 5500-EZ filing notices