An FID number stands for Federal Identification Number, a term commonly used to describe an Employer Identification Number (EIN) issued by the Internal Revenue Service (IRS). It is a unique nine digit number used to identify a business entity for tax reporting, payroll filings, and regulatory purposes in the United States.
Businesses often use the terms FID number, EIN, and FEIN (Federal Employer Identification Number) interchangeably.
An FID number contains nine digits formatted like this:
XX-XXXXXXX
Example: 12-3456789
The first two digits historically represented the IRS processing center where the number was issued, although modern assignment is now largely centralized.
An FID number allows the IRS and other government agencies to track business tax activity.
Businesses typically need an FID number for:
• filing federal tax returns
• reporting payroll taxes
• opening business bank accounts
• applying for business licenses and permits
• hiring employees
• issuing W-2 and 1099 forms
• establishing retirement plans
• applying for business credit
Most organizations operating in the United States require an FID number, including:
• corporations
• partnerships
• limited liability companies (LLCs)
• nonprofit organizations
• trusts and estates
Sole proprietors may also need an FID number if they hire employees, file employment taxes, or establish retirement plans.
Businesses can apply for an FID number directly through the IRS. The process is free.
Online application
The IRS EIN Assistant allows businesses to receive an EIN immediately after completing the application.
Fax application
Submitting Form SS-4 by fax usually results in a response within a few business days.
Mail application
Mail applications may take several weeks to process.
If a business needs to locate its FID number, it can usually be found on:
• previous tax returns
• IRS confirmation letters
• payroll tax filings
• business bank records
• W-2 or 1099 forms
If the number cannot be located, the IRS Business and Specialty Tax Line can assist.
FID number
• identifies a business entity
• used for payroll and tax reporting
• issued by the IRS
Social Security Number (SSN)
• identifies an individual taxpayer
• used for personal tax reporting
• issued by the Social Security Administration
Is an FID number the same as an EIN?
Yes. In most business contexts, FID number and EIN refer to the same identifier issued by the IRS.
Is an FID number public information?
Some EINs appear on public filings and nonprofit disclosures, but businesses should still protect them to prevent identity misuse.
Can a business operate without an FID number?
Some sole proprietors may operate using a Social Security Number, but most businesses need an EIN once they hire employees or open business bank accounts.
How long does it take to get an EIN?
Online applications usually provide an EIN immediately.
An FID number is a core identifier for businesses operating in the United States. It enables organizations to file taxes, hire employees, open financial accounts, and remain compliant with federal regulations. As organizations expand their workforce and HR operations, many also adopt modern people management platforms like Engagedly. You can request a demo to see how performance management, employee engagement, and development tools support growing teams.
