Federal Tax ID Number (EIN): How to Get One Fast
Skip the IRS paperwork. CorpNet prepares and files your Federal Tax ID Number application so you can open a bank account, hire people, and run your business.
What is a Federal ID Number?
A Federal Tax ID Number, also called an Employer Identification Number (EIN) or Tax Identification Number (TIN), is the unique nine-digit number the IRS issues to identify a business for federal tax purposes. It is formatted as XX-XXXXXXX and works like a Social Security Number for your business.
The IRS issues EINs for free, and the number never expires. You will use it to:
- File business taxes
- Open a business bank account
- Hire employees
- Apply for business licenses and permits
- Apply for business credit cards
Using an EIN instead of your Social Security Number on these documents adds a layer of liability and privacy protection for your personal assets.
An EIN is optional if you run a Sole Proprietorship with no employees. It is required by law if your business operates as a C Corporation, S Corporation, Limited Liability Company with more than one member, or Partnership, or if you have employees, withhold taxes from non-wage income, or file certain tax returns.
Do You Need an EIN?
It depends on how your business is structured and what activities you plan to do. The IRS requires an EIN for most business entities. Sole proprietors without employees can usually use their Social Security Number instead, but many still get an EIN for privacy and liability reasons.
Here is the quick answer by entity type:
| Business Type | EIN Required? | Why? |
|---|---|---|
| Multi-Member LLC | Yes, always | The IRS treats multi-member LLCs as partnerships by default and requires an EIN |
| Single-Member LLC | Only if you have employees, have excise tax liability, or elect to be taxed as a corporation | Otherwise the IRS treats it as a disregarded entity and you can use your SSN |
| C Corporation | Yes, always | Required by federal law for all corporations |
| S Corporation | Yes, always | Required for the S-corp election and ongoing tax filings |
| Partnership | Yes, always | Required for partnership tax returns |
| Sole Proprietor | Only if you have employees, establish a qualified retirement plan, or file excise, employment, or alcohol, tobacco, and firearms tax returns | Otherwise you can use your SSN, but most still apply for privacy |
| Nonprofit | Yes, always | Required for 501(c)(3) applications and tax filings |
Sources from IRS.gov: “Single Member Limited Liability Companies”; “Get an Employer Identification Number”; Form SS-4 Instructions, December 2025 revision. CorpNet is a document filing service and cannot provide legal or tax advice. Consult a CPA or attorney for guidance on your specific situation.
Other situations that require an EIN:
- You have employees or plan to hire any
- You withhold taxes on non-wage income paid to a non-resident alien
- You file employment, excise, or alcohol, tobacco, and firearms tax returns
- You operate certain trusts, estates, farmers’ cooperatives, or real estate mortgage investment conduits
Why sole proprietors voluntarily apply for an EIN:
Even when an EIN is not required, many self-employed business owners apply for one. The reason is privacy. Without an EIN, you have to put your Social Security Number on 1099 forms, business credit applications, vendor invoices, and other business documents. An EIN keeps your SSN private and reduces your exposure to identity theft.
Is an EIN Free from the IRS?
Yes. The IRS issues Employer Identification Numbers at no cost through IRS.gov.
So why pay CorpNet? Free is not the same as easy.
The IRS application has narrow hours, strict formatting rules, and rejection codes that send you to the back of the line if you make a single mistake. We handle all of it for you, and you get your EIN faster, with no risk of doing it wrong.
Here is what you are buying:
- A faster path to your EIN. The IRS online tool has limited hours and times out after 15 minutes of inactivity. Submit your information to us anytime, and we handle the IRS filing for you.
- A correctly prepared Form SS-4. The IRS rejects applications with name conflicts, incomplete entries, or formatting errors. We prepare your form right the first time, so you do not lose a week to a resubmission.
- One step in your business setup, not three. If you are forming an LLC or corporation with CorpNet, your EIN application moves through the same workflow as your formation filing. You get everything you need to open a bank account on day one.
- A backup copy of your CP 575 confirmation letter. The IRS does not reissue your CP 575. If you lose it, you have to request a Letter 147C, which can take 30 days or more. We keep a copy on file for you.
- A real person to call if something goes wrong. Filing the IRS application yourself means you handle every IRS callback, rejection notice, and clarification request. With CorpNet, our team handles it.
Customers often choose to pay for our service because their time is worth more than the savings, and because getting it right the first time matters most to them.
Important: CorpNet is a third-party filing service and is not affiliated with the IRS. We file your EIN application as your authorized designee under IRS rules.
How to Get an EIN
There are five ways to apply for an Employer Identification Number. Four go directly through the IRS. The fifth is to let CorpNet handle it for you.
The IRS requires the responsible party on every EIN application to be an individual with a Social Security Number or Individual Taxpayer Identification Number. You can apply for only one EIN per responsible party per day across all methods.
Option 1: Apply online through the IRS
The fastest IRS option. You complete Form SS-4 through the IRS’s online system at IRS.gov and receive your EIN immediately if the application is accepted. Available Mon-Fri 6am to 1am next day, Sat 6am to 9pm, and Sun 6pm to 12am Eastern Time. The session times out after 15 minutes of inactivity and the system rejects applications with name conflicts, formatting errors, or incomplete fields. You must be in the US or US territories with a valid SSN, ITIN, or other EIN as the responsible party.
Option 2: Apply by fax
Fax your completed Form SS-4 to 855-641-6935 if your business is in any of the 50 states or the District of Columbia. International applicants fax to 855-215-1627 from within the US or 304-707-9471 from outside the US.
Include a return fax number on Form SS-4 and the IRS faxes your EIN back within approximately four business days. If you omit the return fax number, the IRS mails the EIN instead, which adds about four weeks.
Option 3: Apply by mail
Mail your completed Form SS-4 to the IRS at the address in the Form SS-4 instructions. The IRS recommends submitting at least four to five weeks before you need the EIN. You will receive your EIN by mail in approximately four weeks.
Option 4: Apply by phone (international applicants only)
If your principal business is outside the US, call the IRS at 267-941-1099 Mon-Fri 6am to 11pm Eastern Time. This is not a toll-free number. The person calling must be authorized to receive the EIN and answer questions about Form SS-4. The IRS issues the EIN during the call.
Option 5: Let CorpNet do everything for you (recommended)
We prepare Form SS-4 to IRS specifications, file the application as your authorized third-party designee, handle IRS follow-up if the application is rejected or flagged, and keep a copy of your CP 575 confirmation letter on file. If you are also forming an LLC or corporation with us, your EIN application is bundled with your formation filing so everything is ready on day one.
Sources: IRS, “Get an Employer Identification Number” (irs.gov); IRS Form SS-4 Instructions, December 2025 revision.
What You Need to Apply for an EIN
Before you start your EIN application, gather the following information. Whether you apply through the IRS directly or have CorpNet file for you, the IRS Form SS-4 application requires the following details.
- Legal name of the business entity (or the individual, for sole proprietors), exactly as it appears on your legal formation documents or Social Security card
- Trade name or “doing business as” (DBA) name if different from the legal name
- Name of the executor, administrator, trustee, or “care of” person if applicable
- Mailing address where you want to receive IRS correspondence
- Physical street address if different from the mailing address (P.O. boxes are not allowed here)
- County and state where the principal business is located
- Full name and SSN or ITIN of the responsible party (the individual who ultimately owns or controls the entity and its funds). Government entity applicants may use an EIN instead
- Type of legal entity (LLC, Corporation, Partnership, Sole Proprietor, Nonprofit, etc.) and the number of LLC members if applicable
- Reason for applying for the EIN (starting a new business, hiring employees, banking purpose, etc.)
- Date the business started or was acquired
- Closing month of your accounting year (typically December)
- Maximum number of employees expected in the next 12 months
- First date wages will be paid (if you have or expect employees)
- Principal business activity and primary products or services
- Third-Party Designee information if you want someone else (like CorpNet) authorized to receive the EIN and answer IRS questions about the application
Most of this information takes a few minutes to gather if you have your formation documents and Social Security card on hand. The harder part is making sure each entry matches existing records exactly. Name mismatches between the responsible party’s legal name and what the Social Security Administration has on file are one of the most common causes of application rejection.
When you order EIN service from CorpNet, we walk you through the same information in a short questionnaire, prepare your Form SS-4 to IRS specifications, and submit the application as your authorized third-party designee. No risk of formatting errors or name conflicts triggering an IRS rejection.
Sources: IRS Form SS-4 Instructions, December 2025 revision (irs.gov).
How Long Does It Take to Get an EIN?
It depends on how you apply. The fastest path is the IRS online tool, which issues your EIN immediately. The slowest is mail, which takes about four weeks.
Here is the timeline by application method:
| Application Method | Time to Receive EIN |
| Online (IRS) | Immediately upon application acceptance |
| Phone (international applicants only) | Immediately during the call |
| Fax with return fax number | Approximately four business days |
| Fax without return fax number | Approximately four weeks (mailed) |
| Approximately four weeks | |
| CorpNet | 1-2 Business Days |
One thing to know about your new EIN. Even when you receive your EIN immediately online, it takes about two weeks before the number is permanently registered in the IRS system. During those first two weeks, you can use your EIN to open a business bank account and apply for licenses, but you cannot use it for electronic tax filings, electronic federal tax payments, or to pass the IRS Tax ID Number matching program.
Your CP 575 confirmation letter. Regardless of how you apply, the IRS mails an official CP 575 confirmation letter within two to three weeks. Save this letter. The IRS does not reissue CP 575 letters if you lose it. The only replacement is a Letter 147C, which can take 30 days or more to receive and requires a separate request through the IRS Business and Specialty Tax Line at 800-829-4933.
Sources: IRS, “Apply for an Employer Identification Number (EIN) Online” (irs.gov); IRS, “How Long Will It Take to Get an EIN” (irs.gov); IRS Form SS-4 Instructions, December 2025 revision.
When Do I Need a New EIN?
You need a new EIN when your entity’s ownership or structure changes. You do not need a new EIN if you just change your business name or address.
You need a new EIN if you:
- Incorporate (change from a sole proprietorship or partnership to a corporation)
- Form a partnership as a sole proprietor
- End an existing partnership and begin a new one
- Change from a partnership or corporation to a sole proprietorship
- Convert an existing single-member LLC to a multi-member LLC by adding owners
- Operate a single-member LLC and become required to file excise or employment tax returns
- Declare bankruptcy as a sole proprietor
- Get a new charter for a corporation from the secretary of state
- Become a corporation’s subsidiary
- Merge and create a new corporation
- Terminate an existing LLC and form a new corporation or partnership
You do NOT need a new EIN if you:
- Change the name of your business (file IRS Form 8822-B for the update)
- Change your business location or add additional locations (file IRS Form 8822-B)
- Operate multiple businesses under one sole proprietorship
- Declare bankruptcy as a corporation or partnership
- Are the surviving corporation after a merger
- Choose to be taxed as an S corporation (the existing corporation or LLC keeps its EIN)
- Reorganize your corporation to change only its identity or location
- Convert your entity at the state level without changing your business structure
- Convert a partnership to an LLC classified as a partnership
- Operate a single-member LLC and do not have employees, do not owe excise tax, and have not elected corporate taxation
- Use your sole proprietor EIN for your single-member LLC and do not elect corporate taxation, do not have employees, and do not owe excise tax
If you are restructuring your business and need both a new entity formation and a new EIN, CorpNet handles both in one workflow. We file your new LLC or corporation formation and prepare your new EIN application together, so your business has everything it needs from day one.
Sources: IRS, “When to get a new EIN” (irs.gov, last updated April 15, 2026); IRS Form SS-4 Instructions, December 2025 revision (irs.gov); IRS Publication 1635, “Understanding Your EIN”; IRS Form 8822-B, “Change of Address or Responsible Party”; IRS Form 2553, “Election by a Small Business Corporation.”
EIN vs SSN vs ITIN vs TIN: What’s the Difference?
A TIN is the umbrella term for all federal tax identification numbers. EIN, SSN, and ITIN are specific types of TINs. Each one serves a different purpose.
Here is how they compare:
| Type: | Format: | Issued By: | Used For: |
| TIN (Taxpayer Identification Number) | Varies by type | Varies | The IRS’s umbrella term for any tax ID number |
| EIN (Employer Identification Number) | XX-XXXXXXX | IRS | Identifying a business for federal tax purposes |
| SSN (Social Security Number) | XXX-XX-XXXX | Social Security Administration | Identifying US citizens and authorized residents for taxes, work, and benefits |
| ITIN (Individual Taxpayer Identification Number) | 9XX-XX-XXXX | IRS | Identifying individuals required to file US taxes but ineligible for an SSN |
A few important clarifications:
- TIN is a category, not a single number. When a tax form asks for your Tax Identification Number “TIN,” it is asking for whichever specific number applies to your situation, usually an SSN, EIN, or ITIN.
- EIN goes by other names, too. FEIN (Federal Employer Identification Number) and Federal Tax ID Number both refer to the same thing as an EIN. The IRS uses all three names interchangeably.
- The Social Security Administration issues SSNs, not the IRS. SSNs are commonly thought of as an IRS number but they are actually issued by a separate agency. The IRS uses them, along with EINs and ITINs, to identify taxpayers on tax returns.
- ITINs are for tax reporting only. An ITIN does not authorize the holder to work in the US, does not qualify them for Social Security benefits, and does not make them eligible for the Earned Income Tax Credit.
- There are two more types of TINs you may have heard of. ATIN (Adoption Taxpayer Identification Number) is a temporary number for children in the adoption process who do not yet have an SSN. PTIN (Preparer Tax Identification Number) is for paid tax preparers. Neither applies to most small business owners.
If you are starting a business and currently using your SSN for business documents, getting an EIN keeps your SSN off 1099 forms, vendor invoices, and credit applications. It is a privacy upgrade as well as a business credibility upgrade.
Sources: IRS, “Employer Identification Number” (irs.gov); IRS, “Taxpayer Identification Numbers (TIN)” (irs.gov); IRS, “Individual Taxpayer Identification Number” (irs.gov); IRS Form W-7 Instructions; IRS Form SS-4 Instructions, December 2025 revision.
Ready to Get Your EIN?
If you are starting a business and ready to focus on running it instead of filing paperwork, let CorpNet take care of your EIN application.
Frequently Asked Questions
Do I need an EIN to open a business bank account?
It depends on the bank and your business structure. Most banks require an EIN for LLCs, corporations, partnerships, and any business with employees. Sole proprietors and single-member LLCs can sometimes open a bank account using just their SSN, but many banks prefer or require an EIN even for these structures.
Do I need an EIN before or after forming my LLC?
Form your LLC first. The IRS explicitly recommends forming your legal entity through your state before applying for an EIN. If you apply for an EIN before your LLC is approved, the EIN may be tied to the wrong entity name or structure, which can cause delays or require a new EIN application later.
Can two people share one EIN?
It depends on what you mean. Co-owners of a single business entity (like a partnership or multi-member LLC) share one EIN that belongs to the business itself. But two separate businesses cannot share an EIN, even if they have the same owners. Each separate legal entity needs its own unique EIN.
Can I have multiple businesses under one EIN?
It depends on your business structure. Sole proprietors can use one EIN for multiple businesses operated under “doing business as” (DBA) names because they are all part of the same individual taxpayer. Each separate legal entity (LLC, corporation, partnership) requires its own EIN, even if you own all of them, or if they are all owned by the same entity.
Does an EIN expire?
No. Once the IRS issues an EIN, it never expires. The IRS does not reassign EINs to other businesses, so your EIN belongs to your business permanently. However, you may need a NEW EIN if your business structure changes, such as converting from a sole proprietorship to a corporation.
Can I cancel or close an EIN?
The IRS does not cancel EINs. Once assigned, an EIN is permanently linked to that business in IRS records. However, you can request the IRS deactivate the business account associated with the EIN. Send a letter to the IRS with your EIN, legal business name, address, and reason for deactivating. You must file all outstanding tax returns first.
How do I find a lost EIN?
Check your CP 575 confirmation letter from the IRS, prior business tax returns, business bank account documents, or business license applications. If you cannot find it in your records, call the IRS Business and Specialty Tax Line at 800-829-4933, Monday through Friday 7am to 7pm local time. The IRS will release your EIN to authorized individuals over the phone.
Can I get an EIN without being a US citizen or resident?
Yes. Non-US residents and individuals without an SSN or ITIN can apply for an EIN by phone, fax, or mail (the IRS online tool is not available to non-residents). See our complete guide to applying for an EIN as a non-US resident for full details here.