Key Takeaways for 2026 Compliance
- 100% Free Service: Applying directly on IRS.gov costs $0 — beware of predatory third-party sites charging $100–$300.
- Instant Issuance: Your 9-digit EIN and downloadable CP 575 confirmation PDF are generated immediately upon completion.
- Operating Window: The IRS online system operates Monday–Friday, 7:00 AM to 10:00 PM Eastern Time (closed on weekends).
- SSN Privacy Shield: Sole proprietors and freelancers can use an EIN on Form W-9 to keep their personal SSN confidential.
- 15-Minute Session Rule: The IRS portal times out after 15 minutes of inactivity; gather all required details before starting.
- Responsible Party Requirement: The individual applicant must own or control the entity and have a valid SSN or ITIN.
- Single-Member LLC Rule: Disregarded entities must enter the owner's legal name on Line 1 of Form W-9 to prevent CP2100 notices.
2. What is an EIN & Who Legally Needs One?
An Employer Identification Number (EIN), also known as a Federal Tax Identification Number (FEIN), is a unique nine-digit number formatted as XX-XXXXXXX assigned by the Internal Revenue Service under 26 U.S.C. § 6109 to identify tax accounts of business entities, employers, estates, trusts, and other organizations in the United States.
When an EIN is Required by Federal Law
- Hiring W-2 employees or withholding federal employment taxes.
- Operating as a Corporation (C-Corp or S-Corp) or Partnership.
- Multi-Member LLCs filing Form 1065 partnership tax returns.
- Opening a dedicated commercial business bank account.
- Administering estates, trusts, non-profits, or plan administrators.
Voluntary EIN for Freelancers & Sole Props
- Identity Protection: Enter your EIN on client Form W-9s to keep your personal SSN off third-party databases.
- Commercial Credibility: Establishes a business identity for trade accounts, vendors, and wholesale suppliers.
- Retirement Accounts: Required to establish a Solo 401(k) or SEP-IRA plan for self-employed individuals.
- Instant Issuance: 100% free and assigned in less than 10 minutes online.
3. IRS System Operating Hours & Time Zones
Unlike typical internet web applications, the official IRS online EIN Assistant tool is tied to strict federal mainframe operating hours. The online application is only accessible during these active windows:
4. Screen-by-Screen Walkthrough of the Official IRS Assistant
When applying at https://sa.www4.irs.gov/modiein/individual/index.jsp, you will progress through five structured screens:
Screen 1: Identify Your Legal Structure
Select your legal entity type. If you are an individual freelancer without state LLC formation, choose Sole Proprietorship. If you have filed Articles of Organization with your state, choose Limited Liability Company (LLC) and enter the exact number of members.
Screen 2: Reason for Applying
Select the primary trigger for this application:
- Started a new business: Most common selection for new LLCs, startups, and self-employed individuals.
- Banking purposes: Opening a business bank account or obtaining merchant credit card processing.
- Hired employees: Employing staff subject to payroll tax withholdings.
- Changed type of organization: Converting from sole proprietorship to LLC or corporation.
Screen 3: Authenticate the Responsible Party
Under Treasury Regulation § 301.6109-1, the "Responsible Party" must be an individual person (not another entity) who controls, manages, or directs the applicant entity and the disposition of its funds and assets.
Screen 4: Physical Location & Business Details
Provide the physical street address where business operations occur. The IRS strictly prohibits P.O. Boxes as the physical business location (although a P.O. Box is permitted as a separate mailing address).
You will also be asked if your business sells gambling devices, operates alcohol/tobacco services, or manufactures heavy highway vehicles. The vast majority of standard businesses answer "No" to all five regulatory questions.
Screen 5: Confirmation Option — Choose "Receive Letter Online"
You are presented with two delivery choices:
5. CP 575 Notice vs. 147C Verification Letter
When your EIN is generated online, the IRS produces an official confirmation notice called Notice CP 575. This document is required by commercial banks to open business checking accounts and merchant payment gateways.
IRS Notice CP 575 (Original)
The original computer-generated certificate created at the exact moment of EIN assignment.
IRS Letter 147C (Replacement)
The official replacement EIN Verification Letter issued by IRS agents upon request.
6. How to Use Your EIN on Form W-9 (Avoid CP2100 Notices)
Once you receive your 9-digit EIN, you will use it to complete Form W-9 (Request for Taxpayer Identification Number and Certification) for clients and hiring companies before receiving payments.
However, entering the wrong combination of legal name and EIN causes an automated IRS Name/TIN Mismatch and triggers Notice CP2100 (B-Notice), requiring the payer to deduct 24% backup withholding from all future disbursements under 26 U.S.C. § 3406.
7. Non-US Residents & Form SS-4 Fax Method
If you are an international founder or non-resident alien without a U.S. Social Security Number or ITIN, you cannot use the IRS online EIN Assistant.
To obtain an EIN for a U.S. company as a non-resident, follow this official paper procedure:
How Foreign Founders Obtain an EIN via Form SS-4 Fax:
- Download official Form SS-4 (Application for Employer Identification Number) from IRS.gov.
- Fill in Line 1 (Legal Name of Entity) and Line 2 (Trade Name).
- On Line 7a, enter the full legal name of the foreign responsible party.
- On Line 7b, write
"Foreign"(or"N/A"). Do not leave this field blank. - Sign and date the certification at the bottom of the form.
- Fax the completed Form SS-4 to the IRS International Operation Fax line: (855) 641-6935 (within the US) or +1 (304) 707-9471 (outside the US).
- Include a return fax number on your cover sheet. The IRS will transmit your assigned EIN and CP 575 notice back to your fax machine within 4 to 7 business days.
8. IRS Error Codes Decoder (101, 102, 109, 114, 115)
If the IRS online tool encounters a validation failure, it displays a numeric reference code instead of an approved confirmation. Here is how to decode and resolve each code:
The entity name closely matches an existing entity in the IRS master file. You must fax Form SS-4 along with your approved state Articles of Organization to (855) 641-6935 so an IRS agent can manually resolve the naming conflict.
The physical street address failed USPS standardization. Verify the exact postal street suffix (e.g., "Street" vs "ST", "Suite 100" vs "STE 100") on tools.usps.com and re-enter.
The Responsible Party name and SSN combination does not match Social Security Administration records. Re-enter your name exactly as printed on your Social Security card (including middle names and hyphenated surnames).
Under IRS regulations, a single responsible party may only be issued ONE EIN per calendar day. Wait until 7:00 AM EST the following business day to submit another application.
9. How to Avoid Paid Third-Party EIN Filing Scams
A large number of commercial websites use Google Ads to rank above the official IRS portal for search terms like "apply for ein online" or "get tax id number".
Red Flags of Paid EIN Third-Party Middlemen:
- Asking for a credit card number: The official IRS EIN application on irs.gov NEVER asks for payment details or credit cards.
- Charging "Processing Fees" ($75 to $350): These companies simply take your data and submit it to the free IRS portal on your behalf.
- URL does not end in
.gov: Always verify that your browser URL bar begins withhttps://sa.www4.irs.gov/orhttps://www.irs.gov/.
Frequently Asked Questions
How much does it cost to get an EIN from the IRS?
Applying for an EIN directly through the official IRS website (irs.gov) is 100% FREE. The IRS charges zero dollars for issuing an Employer Identification Number. You should never pay third-party filing websites charging $50 to $300 to submit Form SS-4 on your behalf.
What are the IRS online EIN application hours?
The IRS online EIN Assistant is available Monday through Friday from 7:00 AM to 10:00 PM Eastern Standard Time (EST / EDT). The online application system is offline on weekends and federal holidays for system maintenance.
How quickly is an EIN issued when applying online?
When you complete the application through the IRS online assistant, your 9-digit EIN is issued immediately upon submitting the final screen. You can download and save your official CP 575 confirmation letter as a PDF on the spot.
Can I get an EIN if I am a sole proprietor without employees?
Yes. Sole proprietors, freelancers, and independent contractors are fully eligible to obtain an EIN from the IRS with zero employees. Using an EIN instead of your personal Social Security Number on client Form W-9s shields your SSN from identity theft and data leaks.
What is the difference between an IRS CP 575 Notice and a 147C Letter?
A CP 575 Notice is the original confirmation letter generated by the IRS computer system when your EIN is first issued; it can only be generated once and cannot be reissued. A 147C Letter is an official replacement verification letter issued by the IRS if you lose your CP 575 notice. You can obtain a free 147C Letter by calling the IRS Business & Specialty Tax Line at 1-800-829-4933.
Can foreign non-US residents without an SSN or ITIN apply for an EIN online?
No. The IRS online EIN Assistant strictly requires the applicant responsible party to enter a valid 9-digit U.S. Social Security Number (SSN) or Individual Taxpayer Identification Number (ITIN). Foreign non-residents without an SSN or ITIN must apply by submitting Form SS-4 by fax to (855) 641-6935 or by calling the IRS International Business Tax Line at +1 (267) 941-1099.
How do I use my new EIN on Form W-9 if I have a Single-Member LLC?
For a Single-Member LLC treated as a disregarded entity, IRS regulations require you to enter the individual owner's personal legal name on Line 1, the LLC name on Line 2, and provide the owner's SSN or owner's Sole Proprietorship EIN in Part I. Putting the LLC name on Line 1 with the LLC's entity EIN triggers an automated IRS Name/TIN mismatch and CP2100 Notice.
What should I do if the IRS Assistant gives me "Reference Number 101"?
Reference Number 101 indicates that the IRS business database found an existing entity with an identical or confusingly similar business name in the same state. This error cannot be resolved online. You must fax a completed Form SS-4 along with a copy of your state-approved Articles of Organization to the IRS at (855) 641-6935.
- Internal Revenue Service (IRS.gov): Instructions for Form SS-4: Application for Employer Identification Number (Rev. December 2023 / Catalog No. 16055N).Official Source ↗
- United States Code (Legal Information Institute): 26 U.S.C. § 6109 — Identifying Numbers for Taxpayer Identification (Internal Revenue Code Section 6109(a)(1)).Official Source ↗
- Code of Federal Regulations (eCFR): 26 C.F.R. § 301.6109-1 — Identifying Numbers & Verification Rules (Treasury Regulations § 301.6109-1).Official Source ↗
- Internal Revenue Manual (IRS.gov): IRM 21.7.13 — Assigning Employer Identification Numbers (EINs) (IRS Internal Revenue Manual Part 21, Chapter 7, Section 13).Official Source ↗
- United States Code (Legal Information Institute): 26 U.S.C. § 3406 — Backup Withholding for Invalid or Missing TINs (Internal Revenue Code Section 3406).Official Source ↗