How To Get A Tax Identification Number For A Trust: A Complete Step-by-Step Guide

To obtain a tax identification number for a trust, you must apply for an Employer Identification Number (EIN) through the IRS, which acts as the trust's unique taxpayer identification. The application can be submitted online for immediate generation, or via fax and mail using IRS Form SS-4. This number is legally required for irrevocable trusts and revocable trusts that have become irrevocable to open fiduciary bank accounts and file annual income tax returns.

Pre-Application Documentation and Trustee Preparation

Acquiring a Taxpayer Identification Number (TIN)—specifically an Employer Identification Number (EIN) in the context of trusts—is a foundational legal step in trust administration. Under United States tax law, a trust is recognized as a distinct legal and tax entity once it becomes irrevocable. While a revocable living trust typically utilizes the grantor's Social Security Number (SSN) during their lifetime, the trust must secure its own unique EIN upon the grantor's death, or if the trust is structured as irrevocable from its inception.

Before initiating the application process with the Internal Revenue Service (IRS), the acting trustee must gather specific, legally binding documents and information. The IRS online system does not allow you to save progress; a session timeout occurs after 15 minutes of inactivity. Having all verified details on hand prevents administrative delays, system rejections, or the accidental creation of duplicate entities.

Pre-Application Checklist

• Essential Documents & Information:

  
  
  
  • The complete, legally executed Trust Agreement (including any amendments).
  • The formal, exact legal name of the trust as written in the trust agreement.
  • The date the trust was established and notarized.
  • The legal name, address, and Social Security Number (SSN) or Individual Taxpayer Identification Number (ITIN) of the Grantor/Settlor.
  • The legal name, mailing address, and SSN/ITIN of the designated Trustee (or the corporate EIN if a bank or trust company is serving as trustee).
  • The designated "Responsible Party" details (must be an individual, typically the trustee or grantor).

• Mandatory Prerequisite Knowledge:

  
  
  
  • Classification under Internal Revenue Code (IRC) Sections 671-678 (identifying whether the trust is a Grantor Trust or a Non-Grantor Trust for tax reporting purposes).
  • Determining the trust's state of jurisdiction, which dictates filing requirements for state-level fiduciary returns.

• Estimated Budget & Processing Benchmarks:

  
  
  
  • Cost: $0.00. The IRS issues EINs free of charge. Avoid third-party filing services that charge fees for this process.
  • Online Application Duration: 15 minutes (immediate document generation).
  • Fax Application Duration: 4 business days.
  • Mail Application Duration: 4 to 5 weeks.

Step-by-Step IRS EIN Application Process for Trustees

To ensure compliance with treasury regulations and to secure a valid tax ID, follow these structured execution steps.

Step 1: Determine the Legal and Tax Status of the Trust

Before filling out any forms, you must analyze the trust agreement to determine its exact structural classification. This classification dictates how you answer critical questions on the IRS application portal.

1. Identify if the Trust is Revocable or Irrevocable: If the grantor retains the power to amend, modify, or revoke the trust, it is a revocable trust. If the grantor has relinquished all control over the assets, or if the grantor has passed away, the trust is irrevocable.
2. Determine the Fiduciary Tax Structure: Irrevocable trusts require their own EINs to file Form 1041 (U.S. Income Tax Return for Estates and Trusts). A revocable trust generally only needs an EIN if the grantor is no longer acting as trustee, if the trust is opening specific commercial accounts, or if the trust has transitioned into an irrevocable status due to the grantor's passing.

Pro-Tip: If you are administering a revocable trust that has split into sub-trusts upon the death of a spouse (such as a Survivor's Trust and a Bypass/Credit Shelter Trust), you must apply for a separate, unique EIN for each distinct sub-trust that is treated as a separate taxpayer entity.

Step 2: Establish the "Responsible Party"

The IRS enforces strict rules regarding who can be named as the "Responsible Party" for any entity application.

1. Understand the Definition: The responsible party is the individual who ultimately controls, manages, or directs the applicant entity and the disposition of its funds and assets.
2. Verify Eligibility: For a trust, the responsible party is typically the grantor or the principal trustee. The IRS will not accept an entity (such as an LLC or a corporate trustee) as the responsible party on the online application unless that corporate entity itself has a valid, active EIN. You must provide this individual’s legal name and SSN, ITIN, or EIN.

Step 3: Complete IRS Form SS-4 (The Draft Phase)

Even if you plan to apply online, completing a physical copy of IRS Form SS-4 (Application for Employer Identification Number) beforehand is highly recommended. This prevents data input errors on the IRS live system.

1. Line 1: Enter the exact legal name of the trust. Use the standard naming convention: [Grantor's Name] Trust dated [Date of Trust Agreement]. For example: "John Doe Irrevocable Trust dated January 15, 2024".
2. Line 3: Enter the name of the active trustee as the "Executor, administrator, trustee, or ‘care of’ name."
3. Line 4a-4b: Provide the mailing address where all IRS tax notices, forms, and correspondence should be sent.
4. Line 7a-7b: Enter the legal name and SSN/ITIN of the responsible party identified in Step 2.
5. Line 9a: Check the box labeled "Trust" and enter the grantor's SSN in the specified field.
6. Line 10: Check the box for the reason for applying. For a new trust, check "Created a trust." If the trust was revocable and is now irrevocable due to the grantor's death, check "Other" and write "Grantor deceased; trust became irrevocable."

Step 4: Submit Your Application to the IRS

Select one of the three primary filing methods based on your timeline, geographic location, and tax credentials.

Method A: The Online EIN Assistant (Preferred)

The IRS online portal is the fastest method to obtain a tax identification number.

1. Navigate to the official IRS website and search for the "EIN Assistant" tool. Ensure you are on a .gov domain to prevent security breaches. The online application is available Monday through Friday from 6:00 AM to 10:00 PM Eastern Standard Time.
2. Select "Trusts" as the entity type under the structural classification options.
3. Confirm that you have read the definition of a trust and click "Begin Application."
4. Input the responsible party information, trust details, and trustee credentials as drafted on your Form SS-4.
5. Review the summary page for typographical errors. Correct any spelling or number errors before submission; once submitted, online errors cannot be changed online.
6. Select "Receive Letter Online" to immediately download your official IRS Form CP 575 (EIN Confirmation Notice) in PDF format.

Warning: Do not close your browser window or lose your internet connection during the final screen. The CP 575 confirmation letter is generated dynamically; if you fail to download it immediately, the IRS will only send a physical copy via standard mail, which can take up to 15 business days to arrive.

Method B: Fax Submission

If you do not have a valid US SSN or ITIN for the responsible party, or if the online system flags your application with an error code, you must apply by fax.

1. Print your completed and signed Form SS-4.
2. Determine the correct IRS fax number. For trustees residing within the 50 states, fax Form SS-4 to (855) 641-6935.
3. Include a cover sheet detailing your return fax number to ensure the IRS can transmit your approved EIN confirmation.
4. Monitor your fax machine; the IRS typically returns the processed form with the assigned EIN written in the top-right corner within four business days.

Method C: Mail Submission

This method is reserved for non-urgent trust setups or situations where fax services are unavailable.

1. Sign and date the completed paper Form SS-4.
2. Mail the document to: Internal Revenue Service, Attn: EIN Operation, Cincinnati, OH 45999.
3. Allow four to five weeks for the IRS to process your paperwork and mail the official EIN confirmation letter to the trust’s registered address.

Tax Classification and Filing Requirements for Different Trust Entities

The IRS treats trusts differently based on their structure, funding sources, and distributive clauses. The table below outlines the relationship between trust types, their assigned tax identification numbers, and corresponding tax filing requirements.

Resolving Common IRS Application Errors and Processing Delays

Applying for a trust tax ID can trigger systemic blocks or processing rejections. Understanding how to handle these technical issues keeps your estate administration on schedule.

Scenario 1: Online "Reference 101" Error Code

• Root Cause: The IRS online system cannot verify the name of the grantor or trustee, or there is a matching-name conflict with an existing entity in the IRS database. This is common when a trust name includes highly generic phrasing or if the grantor’s name matches a flagged taxpayer file.
• Actionable Fix: You cannot bypass this error online. You must apply using the manual paper process. Print your completed Form SS-4 and fax it to the IRS at (855) 641-6935. Write "Reference 101 Response" at the top of your cover sheet to expedite manual processing by an IRS agent.

Scenario 2: System Session Timeout and Data Loss

• Root Cause: The online EIN Assistant has a hard-coded 15-minute inactivity timer. If you pause to read the trust agreement or verify a Social Security Number, the system automatically terminates the session and deletes all entered data.
• Actionable Fix: Do not launch the online portal until you have a fully completed physical draft of Form SS-4 in front of you. Once the application is open, move through the screens continuously. Copying information directly from your pre-filled draft allows you to complete the online portal in under five minutes, well before the timeout limit.

Scenario 3: Application Rejected Due to a Prior EIN on Record

• Root Cause: The IRS database indicates that an EIN has already been assigned to the trust under the same grantor's SSN or a highly similar trust name. This often occurs when a co-trustee or financial planner previously applied for an EIN without notifying the current trustee.
• Actionable Fix: Do not apply for a second EIN, as this creates massive compliance complications. Search all historical legal files, or call the IRS Business and Specialty Tax Line at (800) 829-4933. Once you pass their identity verification and verify your trustee status, the IRS representative will locate the existing EIN and mail you a replacement confirmation letter.

Scenario 4: "Name Mismatch" with Trustee or Grantor Credentials

• Root Cause: The name entered for the trustee or grantor does not match the records held by the Social Security Administration (SSA). This usually happens due to recent marriage name changes, hyphenation discrepancies, or typos in the SSN field.
• Actionable Fix: Verify the spelling of all names against the physical Social Security cards of the parties involved. If a discrepancy exists, input the name exactly as it appears on the Social Security card. If the online system still rejects the application, apply via fax and attach a copy of the trust’s signature pages to prove legal trustee authorization.

Frequently Asked Questions

Can a trustee apply for a trust EIN without a Social Security Number?

Yes, if the trustee is a foreign national who does not have an SSN, they must obtain an Individual Taxpayer Identification Number (ITIN) first, or they can submit Form SS-4 by mail or fax with the SSN field marked "Foreign" or "None." The IRS online system cannot process applications without a US tax ID for the responsible party, meaning the application must be processed manually via fax or mail.

How long does it take for a trust EIN to become active?

While an EIN generated online is issued immediately and can be used to open bank accounts or sign legal agreements, it takes approximately two to three weeks for the number to be fully integrated into all IRS permanent databases. Fiduciaries should wait at least 15 business days before attempting to file electronic tax returns or make electronic federal tax payments (EFTPS) using the new number.

What is the difference between a TIN and an EIN for a trust?

A Taxpayer Identification Number (TIN) is a broad category used by the IRS that includes several types of identification numbers, such as Social Security Numbers (SSNs) and Individual Taxpayer Identification Numbers (ITINs). An Employer Identification Number (EIN) is a specific type of nine-digit TIN used for business entities, estates, and trusts to report tax obligations.

Do I need a new EIN if the trustee of the trust changes?

No, a change in trustee does not require a new EIN because the trust itself remains the same legal entity. However, the trust must report the change of the trustee and any change in the designated responsible party to the IRS within 60 days by filing Form 8822-B, Change of Address or Responsible Party.

Can a revocable trust continue using the grantor's SSN after their death?

No, a revocable trust cannot use the grantor's SSN after their death because the grantor is no longer alive, and the trust has legally transitioned into an irrevocable entity. The successor trustee is legally required to obtain a unique EIN for the trust to manage any income earned by the assets during the administration and distribution process.

Securing Your Trust's Financial Future

Navigating trust administration and tax compliance requires strict attention to detail to protect trust assets and fulfill your fiduciary duties. Partnering with a qualified estate planning attorney or a certified public accountant (CPA) ensures that your trust is correctly established and fully compliant with state and federal tax laws.