Last reviewed October 7, 2026 · By the NYBACS advisory team
Short answer
Before applying for an EIN you need the company's exact legal name as filed, its formation state and start date, its entity type and member count, a mailing address and a non-P.O. box street address, the responsible party's name and SSN or ITIN (or "foreign"), the reason for applying, the accounting year-end, expected employees and the principal business activity. Settle these first, because Form SS-4 errors are slow to correct once the number is issued.
Key takeaways
- File the state formation document first; Form SS-4 line 1 asks for the legal name exactly as it appears on the charter.
- The responsible party must be an individual who ultimately owns or controls the entity, not a company or formation agent.
- A foreign-owned single-member LLC checks "Other" on line 9a and describes itself as a foreign-owned US disregarded entity filing Form 5472, as the instructions specify.
- LLCs state their number of members on line 8b, which tells the IRS whether the default classification is disregarded entity or partnership.
- Line 5 cannot be a P.O. box, and foreign addresses must include the city, province or state, postal code and country.
Line-by-line checklist for Form SS-4
| Line | What to have ready | Watch-out |
|---|---|---|
| 1 | Legal name exactly as on the filed articles | IRS systems drop periods and commas |
| 2 | Trade name or DBA, if any | Leave blank if you do not use one |
| 4a–4b | Mailing address | May be outside the US; this is where IRS letters go |
| 5a–5b | Street address | No P.O. box |
| 6 | Where the principal business is located | Be consistent with line 5 |
| 7a–7b | Responsible party's name and SSN, ITIN or "foreign" | Must be an individual; 7b cannot be blank |
| 8a–8c | Whether it is an LLC, number of members, US-organized | Member count drives default tax classification |
| 9a–9b | Entity type and state of incorporation | Use the exact write-in text the instructions require |
| 10 | Reason for applying | Usually "started new business" |
| 11–12 | Start date and closing month of the accounting year | Use the formation or commencement date |
| 13–15 | Expected employees and first wage date | Only if you genuinely expect payroll |
| 16–17 | Principal activity and products or services | Be specific |
| 18 | Whether the entity has applied before | Answer honestly to avoid duplicates |
Decisions to make before you complete the form
Some lines are not data entry — they record decisions that ripple into every later filing:
- Entity type and classification. A corporation, a disregarded single-member LLC and a multi-member LLC taxed as a partnership file entirely different returns. If an LLC wants to be taxed as a corporation, that is a separate election on Form 8832, not a box on Form SS-4.
- Responsible party. Choose the founder or controlling individual, not whoever is filling in the form.
- Accounting year-end. Most startups use December. A subsidiary may want to align with its foreign parent's year-end; discuss that with your tax adviser before filing.
- Employees. Saying you expect employees can set up payroll filing expectations at the IRS. If you will not run US payroll in the next 12 months, say so.
- Principal activity. "Consulting" or "business" is too vague. "Software development services for US healthcare clients" helps both the IRS and, later, your bank.
Details foreign-owned companies most often lack
Founders outside the US usually have the core facts ready but stall on a few practical items:
- A signer with the right authority. Form SS-4 is signed by a principal officer for a corporation, or by a member or manager for an LLC. A formation agent cannot sign as the company unless properly authorized.
- A return fax number. If you apply by fax, the IRS needs a number it can fax the EIN back to; without one, the confirmation arrives by post.
- A complete foreign address. City, province or state, postal code and country, written the way a US mail system will read it.
- The exact entity description. Foreign-owned single-member LLCs use a specific write-in on line 9a; a generic "LLC" entry is not enough.
Gathering these before drafting saves a second round of emails across time zones.
How these answers are checked later
Form SS-4 answers create the IRS's master record for the company. When you file a return, the IRS expects the form type that matches the entity type it has on file; a multi-member LLC recorded as a partnership that files a Form 1120 instead of a Form 1065 tends to generate correspondence rather than a smooth acceptance.
Banks read the EIN letter alongside your articles and ownership documents, and payment processors match the name and EIN against IRS records. The responsible party you name should be the same person shown as owner or controller on Form 5472, the operating agreement and bank KYC forms.
Correcting a mistake after the EIN is issued
Do not apply for a second EIN to fix an error. Instead:
- Address or responsible party: file Form 8822-B; a responsible party change is due within 60 days.
- Name typos: write to the IRS with the EIN, the correct name and supporting formation documents.
- Wrong entity type or classification: write to the IRS to correct the record, or file Form 8832 if the real need is a classification election.
Corrections take weeks, which is why a ten-minute review of the draft form is worth doing before it is faxed.
Common mistakes to avoid
- Applying before the state has accepted the formation filing, so the name or start date differs from the final certificate.
- Checking "Corporation" on line 9a for an LLC that has not elected to be taxed as one.
- Indicating expected employees when no US payroll is planned, which can trigger payroll filing expectations.
- Describing the principal activity as "business" or "general trading".
- Naming the person who completed the form, rather than the controlling individual, as the responsible party.
- Reapplying after an error instead of correcting the existing record.
Documents and records to prepare
- Filed articles of incorporation or organization, or certificate of formation
- Responsible party's full legal name, passport details and SSN or ITIN if one exists
- Mailing address and street address of the business, with country if outside the US
- Number of LLC members and the ownership structure
- Chosen accounting year-end and any parent-company reporting calendar
- One-sentence description of the principal business activity and main products or services
NYBACS 360° support
How NYBACS helps
- Collects the information above in a short intake and drafts Form SS-4 for your review.
- Checks that the legal name, entity type and responsible party match your formation and ownership documents.
- Advises on year-end and employee entries in light of your parent-company and payroll plans, coordinating with your tax adviser.
- Files the application and handles any IRS correction letters or Form 8822-B updates later.
Frequently Asked Questions
Does the responsible party have to be an owner?
Not necessarily. It must be the individual who ultimately owns or controls the entity and its funds. For most founder-led companies that is the founder, but in a subsidiary it may be a senior officer of the parent.
Can I use a mail-forwarding address as the mailing address?
It can be used as the mailing address if you reliably receive and act on mail sent there. The street address on line 5 must be an actual location and cannot be a P.O. box.
What date should go on line 11?
Usually the date the company was formed or started business. Using a date before the state filing was effective creates an inconsistency with the formation certificate.
Do I need the operating agreement or bylaws signed first?
They are not submitted with Form SS-4, but the decisions they record — members, ownership and who controls the company — should be settled first so the application matches them.
