SS-4 Form Instructions: Line-by-Line Guide
Form SS-4 carries 18 numbered lines and 1 signature block. Line 7b takes Foreign for non-US applicants; line 9a picks the entity type; line 10 picks the reason for applying.
This page walks each line with the exact IRS rule. einnumber.co reviews all 18 fields before filing at $67 Standard or $97 Fast.
What is Form SS-4?
Form SS-4 is the 1 IRS application for an EIN. 18 numbered lines and 1 signature block. Files by online tool (SSN required), fax, mail, or phone. IRS fee: $0. Turnaround: 15 minutes online, 4 to 7 business days by fax, or 6 to 11 weeks by mail.
See the full form on the Form SS-4 canonical page.
What goes on lines 1 to 6 (name and address)?
Line 1: exact state-approved legal name. Line 2: trade name if different. Line 3: executor or care-of name for trusts and estates. Line 4a: US mailing address. Line 4b: foreign address if applicable. Line 5a and 5b: business physical address if different from mailing. Line 6: state of formation.
| Line | Field | Rule |
|---|---|---|
| 1 | Legal name | Match state cert character by character |
| 2 | Trade name (DBA) | Optional |
| 4a | Mailing address | US address OK |
| 4b | Foreign address | Include country and postal code |
| 6 | State of formation | Delaware, Wyoming, etc. |
What goes on line 7a and 7b (responsible party)?
Line 7a: 1 person's full legal name. Not a company. Not a formation agent. Not an accountant. Line 7b: SSN, ITIN, or the word Foreign. Foreign is valid when the responsible party holds no SSN and no ITIN; the IRS returns the EIN by fax at $855-215-1627 within 4 to 7 business days.
What goes on line 8 (LLC classification)?
Line 8a: Yes or No for LLC. Line 8b: number of members (1 for single-member, 2 or more for multi-member). Line 8c: organized in the US Yes or No. Only LLCs fill lines 8b and 8c; non-LLC entities skip both. Read EIN for LLC for LLC-specific rules.
What goes on line 9a (entity type)?
12 entity type options. Sole proprietor, Partnership, Corporation, Personal service corp, Church, REMIC, Trust, National Guard, State/local government, Farmers' cooperative, Estate, Federal government/military. Others go under "Other" with a description. LLCs check "Other" and pick Other and write "Single-Member LLC" or "Multi-Member LLC (Partnership)".
What goes on line 10 (reason for applying)?
9 options: Started new business, Hired employees, Compliance with IRS withholding regulations, Banking purpose, Changed type of organization, Purchased going business, Created a trust, Created a pension plan, Other. Check 1 box. Started new business fits 80 percent of new LLC and corp filings.
What goes on lines 11 to 18 (dates and employees)?
Line 11: start date (state approval date for LLCs/corps). Line 12: closing month of accounting year (December for calendar year). Line 13: highest employee count expected in the next 12 months (3 boxes: agricultural, household, other). Line 14: first date wages paid. Line 15 to 17: business activity and principal product. Line 18: prior EIN if any.
Line 13 needs numbers in all 3 boxes; write 0 for none. Blank boxes trigger IRS rejection 6 to 8 weeks in. 1 employee triggers Form 941 quarterly filings.
What are the reference numbers for Form SS-4?
IRS fax 855-215-1627 non-US, 855-641-6935 US. Mail ZIP 45999. Corporate rate 21 percent. Self-employment 15.3 percent. Social Security 12.4 percent. Medicare 2.9 percent. Additional Medicare 0.9 percent over $200,000. Backup withholding 24 percent. S-corp election 75 days. Classification lock 60 months. Form 5472 penalty $25,000. 60 valid EIN prefixes, 13 unassigned.
| Filing | Deadline | Penalty |
|---|---|---|
| Form 1120 (C-corp) | April 15 | $220 per month |
| Form 1120-S (S-corp) | March 15 | $235 per shareholder |
| Form 1065 (partnership) | March 15 | $235 per partner |
| Form 941 (quarterly) | April 30, July 31, Oct 31, Jan 31 | 2-15 percent |
| Form 940 (annual FUTA) | January 31 | 5 percent per month, cap 25 percent |
| Form 1099-NEC | January 31 | $60 to $310 per form |
| Form 5472 | April 15 | $25,000 minimum |
| Form 2553 (S-corp election) | Within 75 days | Missed election locks 60 months |
Top 5 rejection causes: line 1 name mismatch (30 to 40 percent), company on line 7a (15 to 20 percent), blank line 13 boxes (10 to 15 percent), line 11 start date before state approval (10 percent), no signature (5 to 10 percent). SSN wage base 2026: $184,500.
What else do people ask about SS-4 instructions?
10 more questions covering the 18 lines. Line 1 name match with state record drives 30 to 40 percent of rejections. Line 7b takes Foreign for non-US applicants. Line 13 requires numbers in all 3 boxes; blanks trigger rejection.
How many lines does Form SS-4 have?
18 numbered lines plus 1 signature block. Lines 1 to 6 cover the entity name and mailing address. Line 7a to 7b cover the responsible party. Line 8a covers LLC classification. Line 9a covers entity type. Line 10 covers the reason for applying. Lines 11 to 18 cover start date, closing month, employees, and business activity.
What goes on line 1 of Form SS-4?
The exact state-approved legal name of the entity. Character-for-character match with the state formation certificate. "LLC" versus "L.L.C." reads as 2 different entities to the IRS. Line 1 name mismatch is the #1 cause of Form SS-4 rejection, driving 30 to 40 percent of rejected filings.
What goes on line 7a and 7b?
Line 7a: the responsible party's full legal name. The IRS accepts 1 person, not a company. A parent LLC, formation agent, or accountant fails. Line 7b: SSN, ITIN, or the word Foreign. Foreign works for non-US applicants; the IRS returns the EIN by fax within 4 to 7 business days at 855-215-1627.
What goes on line 8a for LLCs?
Line 8a asks if the entity is an LLC. Check Yes. Line 8b asks the number of LLC members: 1 for single-member LLC, 2 or more for multi-member LLC. Line 8c asks if the LLC was organized in the United States (Yes or No). Line 8 rules apply only to LLCs; non-LLC entities skip lines 8b and 8c.
What goes on line 9a (entity type)?
Line 9a lists 12 entity type options. LLCs check "Other" and write "Single-Member LLC" or "Multi-Member LLC (Partnership)". C-corps check Corporation. S-corps check Corporation and file Form 2553 separately within 75 days. Sole proprietors check Sole proprietor. Trusts check Trust. Estates check Estate.
What goes on line 10 (reason for applying)?
Line 10 lists 9 options. Most common: "Started new business" for newly formed LLCs and corps, "Hired employees" for existing entities adding payroll, "Banking purpose" for entities opening a business account, "Changed type of organization" for entity conversions. 1 selection required; check only 1 box.
What goes on line 11 (start date)?
The date the entity legally started. For LLCs and corps, use the state approval date printed on the formation certificate. A start date earlier than the state approval date gets the form rejected 6 to 8 weeks later. Sole proprietors use the date they began business operations. Trusts and estates use the date of trust/estate creation.
What goes on line 13 (highest number of employees)?
All 3 boxes require a number, not a blank. Line 13a Agricultural: 0 if no farmworkers. Line 13b Household: 0 if no household employees. Line 13c Other: 0 if no other employees. Blank boxes trigger rejection. 1 employee triggers Form 941 quarterly filings and Form 940 annual FUTA at January 31.
Who signs Form SS-4?
The responsible party listed on line 7a signs on the signature line below line 18. Third Party Designees (line 8) do not replace the responsible party signature. Digital signatures are not accepted on fax or mail filings; the IRS requires a wet ink signature. Unsigned forms get returned unprocessed within 4 to 6 weeks.
What are the top 5 SS-4 rejection causes?
1. Line 1 name mismatch with state record (30-40 percent of rejections). 2. Company on line 7a instead of person (15-20 percent). 3. Blank line 13 boxes (10-15 percent). 4. Line 11 start date before state approval (10 percent). 5. No signature (5-10 percent). Fix and refile via fax to 855-215-1627; wait restarts from day 0.