How to obtain an EIN depends on your profile: If you have a Social Security Number (SSN) or International Trademark Number (ITIN) and a US address, apply for the... EIN via the IRS online portal and receive the number during the same call.
If you are an international applicant without a Social Security Number (SSN) or International Trademark Number (ITIN), the process is different: phone or fax, with a response within a few days, never immediately. The difference between the two scenarios determines all your planning, and ignoring it is the most common cause of delay.
In summary:
- Those who do not have an SSN or ITIN must opt for telephone, fax or mail, as the online portal only accepts applicants with these numbers.
- Completing the SS-4 form fully and correctly, especially the lines for the person responsible and the reason for the request, avoids delays and errors in service.
- Applying for an ITIN before an EIN is only worthwhile if the person responsible already has this document, as international processing can take 9 to 11 weeks.
- Diversifying request methods or attempting multiple requests simultaneously increases the risk of delays due to duplicate information or system conflicts.
- For complex corporate structures or when there is urgency, specialized support helps avoid mistakes and speeds up the EIN registration process.
Index
- How to obtain an EIN: a step-by-step guide to completing Form SS-4 without errors.
- How to obtain an EIN: identification documents, ITIN or SSN
- How to obtain an EIN as an international applicant: by phone, fax, or mail.
- Common mistakes that delay obtaining an EIN and how to fix them.
- Planning how to obtain an EIN: apply for an ITIN beforehand or go straight to the phone?
- How Naventia supports you in obtaining an EIN.
- What really matters when it comes to obtaining an EIN?
- When is it worth hiring support to learn how to obtain an EIN and open your company in the USA?
- Frequently Asked Questions
- Sources
Step-by-step guide to completing Form SS-4 without errors.
Before calling the IRS or sending any faxes, complete Form SS-4 in full, following the updated instructions on the form. This document is the basis for all EIN applications, whether submitted online, by phone, fax, or mail, and incomplete completion is the leading cause of processing delays.
Some SS-4 lines require extra caution:
- Line 7a (responsible party): It needs to be a real individual with authority over the entity, never a name put there just for the sake of appearances.
- Line 9a (reason for applying): Describe the real reason, such as opening a new company, hiring employees, or changing the company's corporate structure.
- Main activity: Describe the main business activity in simple and specific terms, avoiding overly generic categories.
- Third-party designer: If another person, such as an accountant or consultant, is authorized to receive the EIN on your behalf, this section must be signed and completed.
O responsible party This refers to the person the IRS considers responsible for the entity for tax purposes. According to IRS guidelines on responsible parties and nominees, using a nominee without real authority over the company violates the agency's guidelines and creates a compliance risk that may surface months later, when it is too late to correct the issue without cost.
Before calling or submitting the form, please check:
- The SS-4 form is complete, with no blank fields that would generate questions from the agent.
- Do you know the correct time zone (Eastern US Time) to call within the service window?.
- You have a fax number available to receive EIN confirmation.
- The signature of the responsible party is required if the process demands physical submission.
Pro tip: Have the SS-4 form on screen or printed out during your call with the IRS: the agent usually asks you to read the answers directly from the form, and having everything ready prevents the call from being interrupted for later resubmission.
Before moving on to the next step, it's worth reviewing what still needs organizing in your operation and checking out the materials in the BibliOWLteca — a guide and resources for entrepreneurs. We've compiled this reasoning in... Checklist of decisions to make before applying for an EIN., which helps to see the process beyond the form itself.
Identification documents: when you need an ITIN or SSN
The EIN identifies the company to the U.S. Internal Revenue Service, similar to the role of the CNPJ in Brazil, but applied to entities and also to individuals acting as employers.
The SSN is the social security number for citizens and residents authorized to work in the United States. The ITIN exists for those who need a tax identification number but are not entitled to an SSN, as is the case for most Brazilian entrepreneurs.
This distinction matters because the online EIN application is only available to those who already have a SSN or ITIN and legally reside or operate in the United States. Without one of these numbers, the portal simply won't process the application, and you'll need to proceed by phone, fax, or mail.
For those who need to apply for an ITIN from abroad, the process involves Form W-7, with original or certified copies of identification documents.
Processing an ITIN requested from abroad takes 9 to 11 weeks during peak season., According to the IRS itself, this makes this step a critical planning point, not just a detail to be filled out.
An alternative that reduces risk is to use a Certifying Acceptance Agent, known as a CAA, which authenticates documents in person and returns the originals during the same appointment, eliminating the need to send them via international mail. When the company's responsible party does not have an SSN or ITIN, this step ceases to be optional and becomes a condition for the entire opening timeline.
How do international applicants obtain an EIN by phone, fax, or mail?
Those outside the United States who do not have a SSN or ITIN follow a different path than the online portal, as described in the official Form SS-4 instructions. This path has three variations, and choosing the correct one avoids weeks of unnecessary waiting.
- Phone call: The number is 267-941-1099, with service available from 6 a.m. to 11 p.m. Eastern Time, Monday through Friday. Have the SS-4 form completed before dialing, because the operator will ask questions directly from the form.
- Fax: For international applicants, the Fax-TIN numbers are 855-215-1627 (within the United States) or 304-707-9471 (outside the United States), as per the instructions on where to send Form SS-4. Responses typically take about 4 business days.
- Mail: Sending the physical document to the IRS international operations address in Cincinnati is the slowest method, with an approximate processing time of 4 weeks until the number is issued.
If, during the call, the agent asks you to send the signed SS-4 form within 24 hours, treat this deadline as non-negotiable and record the date the request was opened. This record serves as proof should it be necessary to resume service later.
Pro tip: Choose a single method of contact and follow through to the end before trying another: opening the same request by phone and then by fax, for example, often creates confusion at the IRS and delays processing instead of speeding it up.
Common errors that delay issuance and how to correct them.
The most frequently cited error by those applying for an EIN is the so-called... Error 101, This appears when the system identifies a potential name conflict or existing data for that entity or responsible party.
According to Taxpayer Advocate Service, The practical correction sequence is: review the SS-4 for inconsistencies in the company name, confirm that the responsible party is correct, and wait for the processing window before seeking manual review or professional support.
Other recurring problems:
- SS-4 with incomplete fields, especially the line for the reason for the request or the main activity.
- The responsible party is listed as a nominee, without actual authority over the company, which contradicts IRS guidelines on responsible parties.
- Multiple applications opened for the same entity using different methods, generating duplication and requiring manual review before any EIN can be confirmed.
- Failure to respond within the deadline requested by the IRS when additional documentation is requested.
If you have already opened more than one application by mistake, do not attempt to open a third: contact the IRS through the same channel used in the first attempt and explain the duplication before insisting on another method.
Pro tip: When a case involves more than one entity, international corporate structure, or responsible party outside the United States, it is worthwhile to seek support from specialized consultants or an Acceptance Agent before attempting to resolve Error 101 on your own, because each extra attempt without technical guidance tends to add another layer of manual review.
Planning: request ITIN before EIN or go straight to the phone.
The correct sequence depends on who is the responsible party in your company. If that person already has an SSN or ITIN, the online EIN application is usually the fastest way. If they don't have either, you need to decide whether it's worth waiting for the ITIN before proceeding or going directly through the IRS international phone line.
- Applying for an ITIN first only makes sense if you also need it for other tax obligations, as processing from abroad takes 9 to 11 weeks during peak periods.
- If the immediate goal is simply to open the company and begin operations, following up by phone or fax with the IRS tends to be faster than waiting for the ITIN to be issued first.
- Using a CAA to authenticate documents reduces the risk of losing originals sent via international mail and usually speeds up the verification process.
- On forms that require the identification number before official issuance, it is common to mark "Applied For" while the EIN is still being processed, provided the institution accepts this status.
How does Naventia support this process?
We offer support in completing Form SS-4, assistance in communicating with the IRS through appropriate channels for international applicants, and help with document authentication at Acceptance Agents when necessary.
- We assist in defining the corporate structure prior to the EIN application, ensuring the responsible party is properly identified.
- We advise contacting the IRS by phone or fax to minimize errors that could lead to rework.
- We assist in connecting the EIN process with opening a US bank account, which usually depends on obtaining this number.
- We provide tax and legal risk analysis from the outset, considering that decisions at this stage impact the company's structure.
Specialized support can streamline the process, making time zone differences, IRS office hours, and documentation requirements manageable steps.
What really matters in this process
Most content about EIN treats the form as minor bureaucracy, something that can be resolved in an afternoon. In practice, the factor that determines the total processing time is not the form itself, but the definition of the responsible party and the choice of a single channel of contact with the IRS.
Those who waste time in this process almost always make the same mistake: they try several approaches simultaneously, submit an online application that gets rejected, call the IRS without the SS-4 form ready, and then send a fax to "be sure." This haste creates exactly the duplication that delays everything.
If you are outside the United States and without a Social Security Number (SSN) or International Trademark Number (ITIN), accept from the outset that the way to go is by phone or fax, not the online portal. Prepare the SS-4 form carefully, choose a channel and follow it through to the end before trying another. This process discipline is worth more than any shortcut found in forums.
— Flavio Inacarato
When is it worthwhile to hire specialized support to open your business in the USA?
For those with a simple corporate structure, with a defined responsible party and all documentation in order, following the step-by-step process alone usually works. The calculation changes when there is more than one partner, an international structure, the need to open a bank account in parallel, or a real urgency to start operating.
In these cases, we take care of all the necessary document preparation, communication with the IRS and Acceptance Agents, and the integration of EIN, account opening, and tax structure, so you don't waste time correcting errors that could have been avoided during the initial contact.
- Entities with more than one partner or an international structure benefit from a prior review by the responsible party before applying for an EIN.
- Those who need to open a bank account next benefit from coordinating both processes from the start.
- Those who have received Error 101 or had a duplicate request usually resolve it faster with technical support than by trying again on their own.
Get to know our Business setup and structuring services in the United States. And understand which path makes sense for your situation before taking the next step.
Frequently Asked Questions
How to obtain an EIN: Is an EIN the same as a CNPJ?
They are not identical, but they serve a similar function: the EIN identifies the company for tax purposes in the United States, just as the CNPJ identifies the company for the Brazilian Federal Revenue Service. The rules for issuing, using, and the responsible agencies are different between the two countries.
What is a company's EIN and how do you obtain an EIN?
The EIN is the tax identification number assigned by the IRS to most entities operating in the United States, including businesses, and also to individuals acting as employers. It is required for filing taxes, making tax deposits, and opening business bank accounts.
How to obtain an EIN: how to get an ITIN number while in Brazil?
The ITIN is requested using Form W-7, with original identification documents or a certified copy submitted to the IRS. Processing from abroad takes 9 to 11 weeks during peak periods, and using a Certifying Acceptance Agent avoids the need to mail original documents.
How to open an LLC in the US and how to obtain an EIN?
Opening an LLC involves choosing the state of registration, defining the corporate structure, and, after incorporation, applying for an EIN to operate legally. We detail this entire process in [link/resource]. A guide to opening and structuring businesses for Brazilians..
Sources
- Employer identification number | Internal Revenue Service
- Getting an EIN | Taxpayer Advocate Service
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