A Guide to Filling Out Form SS-4: Details Instructions

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A Guide to Filling Out Form SS-4: Details Instructions

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Form SS-4 is used to apply for an Employer Identification Number (EIN), a nine-digit number assigned by the Internal Revenue Service (IRS) for tax filing and reporting purposes. This number is essential for employers, sole proprietors, corporations, partnerships, estates, trusts, and other entities. Whether you are starting a new business or a sole proprietor without employees, you will likely need to apply for an EIN using Form SS-4.

Our form ss-4 instructions guide will help you complete the form effortlessly. We provide a step-by-step walkthrough and emphasize key considerations to ensure a smooth application process.

Who Needs Form SS-4?

Form SS-4 is utilized to apply for an Employer Identification Number (EIN). While primarily for employers, many other entities and individuals may also need an EIN for tax filing and reporting purposes.

Who Needs an EIN?

·         Businesses and Sole Proprietors: Any business, including sole proprietors, corporations, and partnerships.

·         Estates and Trusts: Estates of decedents and various trusts.

·         LLCs: Limited liability companies with employees or excise tax reporting obligations. LLCs without employees that file a Schedule C do not require an EIN, but may still choose to obtain one.

Criteria for Filing Form SS-4:

1.   Businesses or individuals hiring employees.

2.   Corporations and partnerships.

3.   Entities paying employment taxes (Social Security, Medicare).

4.   Businesses paying excise taxes.

5.   Businesses involved in alcohol, tobacco, and firearms.

6.   Entities withholding taxes on income paid to non-resident aliens.

7.   Businesses or individuals with a Keogh plan (qualified retirement plan).

If you fall into any of these categories, you will need to fill out form ss-4 to obtain an EIN.

How to Prepare for Completing Form SS-4

Before fill out form ss-4, take the following steps to ensure a smooth application process:

How to Prepare for Completing Form SS-4
How to Prepare for Completing Form SS-4

1.   Confirm the Need for an EIN: Verify that your business or entity requires an Employer Identification Number.

2.   Determine Your Business’s Legal Name: Ensure you have the correct legal name for your business.

3.   Check for a Trade Name: Identify if your business has a trade name (DBA) that differs from its legal name.

4.   Identify Business Structure: Determine if your business is a corporation, partnership, or LLC.

5.   Gather Mailing Address Information: Have the accurate mailing address of your business ready.

6.   Collect Responsible Party Information: Gather information about the individual responsible for the business, including their tax ID number.

7.   Know the Reason for Applying: Clearly define the reason you are applying for an EIN.

8.   Employee and Wage Information: Determine the number of employees and the date when wages were first paid.

9.   Form 944 Consideration: Decide if you will file Form 944, intended for small businesses with few employees and less than $1,000 in annual employment taxes.

10.   Business Start Date and Accounting Year: Know the start date of your business and the closing month of your accounting year.

If any of this information is unknown or if your business has not yet been established, wait until you have all the necessary details before fill out form ss-4.

6 Steps to Complete Form SS-4

Before fill out form ss-4 you need to know that Form SS-4 is divided into three main sections: general information, business type, and other business information.

Step 1: Gather Necessary Information

Before you start, collect all relevant business information. Refer to the list of required details to ensure you have everything ready.

 Step 2: Complete the General Information Section

·         Line 1: Enter the legal name of your business or entity.

·         Line 2: Enter the trade name (DBA) if it differs from the legal name.

·         Line 3: For trusts or estates of decedents, provide the trustee’s name or the executor’s name. For applicants with a designated person to receive tax information, enter their name as the “care of” person.

·         Line 4a–b: Enter the business’s mailing address or the “care of” person’s address if applicable.

·         Line 5a–b: Enter the physical address if it differs from the mailing address.

·         Line 6: Enter the primary location of the entity.

·         Line 7a–b: Enter the responsible party’s full name and Social Security number or taxpayer identification number. This person manages the business, its funds, and its assets.

 Step 3: Complete the Business Type Information Section

·         Line 8: Indicate if the entity is an LLC.

·         Line 9: Specify the type of entity (e.g., sole proprietor, corporation, partnership, estate, trust, plan administrator, government entity).

 Step 4: Complete the Other Business Information Section

Complete the Other Business Information Section
Complete the Other Business Information Section

·         Line 10: Select the reason for applying for an EIN (e.g., starting a new business, hiring employees, banking purposes).

·         Line 11: Enter the date the business was started.

·         Line 12: Enter the closing month of the business’s fiscal year (typically December for a calendar year).

·         Line 13: Provide the highest number of employees expected in the next 12 months. Enter “0” for sole proprietors with no employees.

·         Line 14: Indicate if you plan to file IRS Form 944 for small businesses with less than $1,000 in annual employment taxes.

·         Line 15: Enter the date your business first paid wages or annuities.

·         Line 16: State the primary activity of your business (refer to IRS’s Instructions for Form SS-4 for examples).

·         Line 17: Describe the primary activity of your business in more detail.

·         Line 18: Indicate if the applicant has previously applied for an EIN.

 Step 5: Sign the Form

·         Individual Applicants: Sign the form yourself.

·         Corporations: The president, vice president, or another principal officer must sign.

·         Partnerships, Government Entities, and Unincorporated Organizations: A responsible and duly authorized member or officer must sign.

·         Trusts or Estates: The fiduciary must sign.

 Step 6: Submit Your Form SS-4

You can submit Form SS-4 through the IRS’s online application, by fax, or by mail. Online applications provide immediate EINs and must be completed in one session, which expires after 15 minutes. Phone applications are available only for international applicants.

For online applications, have all your information ready in advance to avoid session timeouts.


Filling out Form SS-4 is essential for obtaining an EIN, crucial for various tax and business purposes. Our detailed instructions guide you through each step to ensure accuracy. If you need expert assistance, visit Aquifer CFO for professional help. Following these form SS-4 instructions will streamline the process, ensuring you have all the necessary information and submit your application correctly.


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