By Legal Radar 
Imagine this: You have just been named trustee of a family trust. Assets need transferring into a bank account, tax forms are stacking up, and someone asks for the trust’s tax ID. You freeze. Is it the grantor’s Social Security number? Do you need something new? And how long will that take?
These questions hit many people in the same spot. Whether you created a revocable living trust years ago, just inherited assets through an irrevocable trust, or stepped into the role of executor or successor trustee after a death, understanding the Trust Tax ID Number is essential. This number, formally an Employer Identification Number or EIN issued by the IRS, acts as the trust’s unique identifier for tax and banking purposes.
In this guide, you will learn exactly what a Trust Tax ID Number is, when a trust requires one (and when it does not), how the rules differ for revocable versus irrevocable trusts, and the free, straightforward steps to apply for one through the IRS. We will clear up common mix-ups between SSN and EIN use, walk through opening a trust bank account, and cover tax filing basics like the fiduciary tax return and Schedule K-1. By the end, you will have practical next steps you can take today.
What Exactly Is a Trust Tax ID Number?
A Trust Tax ID Number is the nine-digit Employer Identification Number (EIN) that the Internal Revenue Service assigns to a trust. It works much like a Social Security number does for an individual, but it identifies the trust as a separate entity for federal tax reporting, banking, and other official purposes.
You will see it written in the format XX-XXXXXXX. Banks ask for it when you open a trust bank account. Brokerages need it for investment accounts titled in the name of the trust. The IRS expects it on Form 1041, the U.S. Income Tax Return for Estates and Trusts, and on the Schedule K-1 tax forms that go out to beneficiaries.
Importantly, the name “Employer Identification Number” can mislead people. Trusts rarely have employees. The IRS simply uses the same EIN system for trusts, estates, corporations, partnerships, and other entities that need their own tax identity.
Not every trust gets its own EIN right away. The deciding factor is whether the IRS treats the trust as a separate taxable entity or as an extension of the person who created it (the grantor). That brings us to the heart of the rules.
When Does a Trust Need Its Own Tax ID Number?
The short answer depends on the type of trust and whether the grantor is still living.
Revocable Living Trusts While the Grantor Is Alive
Most people start with a revocable living trust. As long as the grantor is alive and competent, the IRS almost always treats this as a grantor trust. All income, gains, losses, and deductions flow through to the grantor’s personal tax return. The trust uses the grantor’s Social Security number. No separate Trust Tax ID Number is required for federal tax purposes.
This setup keeps life simple. Interest from a savings account titled in the trust name still shows up on the grantor’s Form 1040. Capital gains from sold investments get reported the same way. The trust itself does not file Form 1041.
Some banks still request an EIN even for a living revocable trust. They can do that as a matter of their own policy. If that happens, you can apply for one. Getting the number does not change how you report the income. It still belongs on the grantor’s personal return.
Irrevocable Trusts
An irrevocable trust is different from day one in most cases. Once the grantor gives up the power to revoke or change the trust, the IRS usually sees it as a separate taxpayer. That means the trust needs its own EIN right away.
There is a limited exception. Some irrevocable trusts are still structured as grantor trusts under specific tax rules (often called intentionally defective grantor trusts). In those situations the grantor continues to pay the tax on the trust’s income, and the trust may be able to use the grantor’s SSN. These arrangements are technical. Most ordinary irrevocable trusts created for asset protection, Medicaid planning, or special needs purposes need their own EIN and file their own returns.
After the Grantor Dies: The Big Change
This is the moment that catches many families off guard. When the grantor of a revocable living trust dies, the trust becomes irrevocable by operation of law. The deceased person’s Social Security number can no longer serve as the trust’s tax ID. The successor trustee must obtain a new Trust Tax ID Number promptly.
Income earned after the date of death belongs to the trust (or the estate, depending on elections made). Banks and investment firms will require the new EIN before they will retitle accounts or open new ones. Tax reporting shifts to Form 1041.
The same rule applies if the trust holds only non-income-producing assets at the moment of death. Once any income starts flowing, or once you need to open accounts, the EIN becomes necessary.
Other Situations That Trigger the Need for an EIN
A few additional triggers exist:
- The trust has employees or must withhold taxes.
- The trust makes payments to non-resident aliens that require withholding.
- You elect certain optional reporting methods for a grantor trust.
- State tax or banking rules demand a separate number even when federal rules do not.
If you are unsure about your specific trust, the safest move is to review the trust document with an estate planning attorney or tax professional who understands fiduciary tax return rules.
Trust Tax ID Number vs SSN: Clearing Up the Confusion
Many people assume every trust needs its own number from the start. Others think they can keep using the grantor’s SSN forever. Both assumptions create problems.
While the grantor is alive and the trust is revocable, the grantor’s SSN is the correct identifier in most cases. Using an EIN when one is not required does not hurt tax reporting, but it is unnecessary paperwork.
Once the trust becomes a separate taxpayer, continuing to use the grantor’s SSN is incorrect and can create matching problems with the IRS. Banks may refuse to open or maintain accounts. Tax forms may get rejected.
Think of it this way: your personal SSN identifies you. The Trust Tax ID Number identifies the trust as its own legal and tax entity. Mixing the two after the point of separation confuses everyone downstream, from the bank teller to the IRS computer system.
How to Get a Trust Tax ID Number: Free IRS Application Steps
The good news is that applying for an EIN costs nothing when you go straight to the IRS. Third-party websites that charge fees simply submit the same free application and keep the difference. The Federal Trade Commission has warned consumers about these services.
You have three main options: online (fastest), fax, or mail. Online is available only if the principal place of business is in the United States or a U.S. territory and the responsible party has a valid SSN or ITIN.
Step 1: Gather the Information You Will Need
Before you start, collect:
- The exact legal name of the trust as it appears in the trust document
- The date the trust was created or became irrevocable (often the grantor’s date of death)
- The mailing address where the trust should receive IRS correspondence
- The name and SSN or ITIN of the responsible party
- The type of trust (revocable that has become irrevocable, irrevocable, etc.)
For trusts, the responsible party is typically the grantor, owner, or trustor. After death, the successor trustee usually fills this role because that person now controls the assets. The responsible party must be an individual, not another entity, except in limited government cases. Nominees with only temporary authority cannot apply.
Step 2: Apply Online for Immediate Results
Go to the official IRS page for obtaining an EIN. The online tool walks you through a series of questions that mirror Form SS-4.
Select “Trust” as the entity type. Indicate the reason for applying (created a trust, or changed type of organization after the grantor’s death). Enter the trust name exactly. Provide the responsible party’s information.
Complete the session in one sitting. The system times out after 15 minutes of inactivity. When you finish, the IRS issues the EIN on the spot. Print or save the confirmation notice (often called the CP 575). Keep that document with the permanent trust records. Banks and tax preparers will ask for it.
The online system is available most hours: Monday through Friday from 6:00 a.m. to 1:00 a.m. Eastern the next day, Saturday 6:00 a.m. to 9:00 p.m., and Sunday 6:00 p.m. to midnight. You may apply for only one EIN per responsible party per day.
Step 3: Alternative Methods if Online Is Not Available
If the online tool does not work for your situation, complete IRS Form SS-4.
Fax the completed form to the number listed in the current instructions (commonly 855-641-6935 for domestic applicants). Include a return fax number. The IRS typically responds with the EIN in about four business days.
Mailing Form SS-4 takes longer, roughly four weeks, and high volume can extend that timeline. Send it to the address shown on the form instructions.
International applicants follow different fax or phone procedures listed on the IRS site.
How Long Does It Take?
Online applications produce the number immediately. Fax takes a few business days. Mail takes about a month. Once issued, you can use the EIN right away for most purposes, including opening a trust bank account. Electronic filing and certain matching programs may need up to two weeks for the number to fully propagate in IRS systems.
Opening a Trust Bank Account with Your New EIN
Once you have the Trust Tax ID Number, take it to the bank along with:
- The original or certified copy of the trust document (or the relevant pages naming the trustee and powers)
- Your personal identification
- Any required certification of trust form the bank provides
- The EIN confirmation letter
Most banks will title the account in the name of the trust, for example “The Jane Doe Revocable Living Trust dated January 15, 2018, John Smith, Trustee.” They will link the account to the EIN rather than anyone’s personal SSN.
This step protects the trust assets and creates a clean paper trail for accounting and tax reporting. Do the same with brokerage accounts and any other financial institutions holding trust property.
Tax Filing After You Have the EIN
A trust that is a separate taxpayer must file Form 1041 if it has gross income of $600 or more, any taxable income, or a nonresident alien beneficiary. The return is due on the 15th day of the fourth month after the end of the trust’s tax year (usually April 15 for calendar-year trusts).
When the trust distributes income to beneficiaries, the trustee issues a Schedule K-1 (Form 1041) to each recipient. The K-1 shows the beneficiary’s share of income, deductions, and credits. Beneficiaries then report those amounts on their personal returns. The trust itself may pay tax on undistributed income, often at compressed rates that reach the highest brackets quickly.
Grantor trusts that still use the grantor’s SSN generally do not file Form 1041. Everything stays on the personal return.
Keep careful records of income, expenses, distributions, and the EIN confirmation. These documents make the annual fiduciary tax return far easier and protect you if the IRS or beneficiaries ever ask questions.
Common Pitfalls Trustees Should Avoid
Several mistakes appear again and again:
- Waiting too long after the grantor’s death to apply for the EIN. Income continues to arrive, and accounts need updating.
- Using a third-party service that charges for a free IRS process.
- Entering the trust name incorrectly on the application. Match the trust document exactly.
- Continuing to use the deceased grantor’s SSN on post-death accounts or tax forms.
- Assuming every irrevocable trust automatically needs an EIN without checking grantor-trust status.
- Forgetting that each separate trust needs its own EIN. One trustee managing three trusts still needs three numbers.
If the trust holds only non-income-producing assets such as a personal residence with no rental income, the filing threshold may not be met, but the EIN is still usually required for account titling and eventual sale or transfer.
Working with Professionals
While the application itself is free and relatively simple, the surrounding decisions often benefit from expert help. An estate planning attorney can confirm whether your trust is still a grantor trust, help with the Section 645 election that can treat a qualified revocable trust as part of the estate for a period of time, and guide distribution timing. A CPA or enrolled agent experienced with fiduciary returns can prepare Form 1041 and the related K-1s correctly.
These professionals also help you avoid state-level quirks. Some states have their own filing thresholds or tax rules that differ from the federal ones.
Putting It All Together: Practical Next Steps
If you are setting up a new irrevocable trust, apply for the EIN as soon as the trust is funded and before you open accounts. If you are the successor trustee of a revocable trust after the grantor’s death, treat obtaining the EIN as one of your first administrative tasks. Gather the trust document, the death certificate if needed for the application, and the responsible-party information, then complete the online form during available hours.
Once you have the number, update every financial institution, retitle assets as required by the trust, and calendar the Form 1041 due date. Maintain a simple ledger of income and expenses from day one.
The Trust Tax ID Number is not mysterious once you understand the grantor-trust rules and the moment a trust becomes a separate taxpayer. With the free IRS process and a clear picture of when the number is required, you can move forward with confidence.
Frequently Asked Questions
Does a revocable trust need a Trust Tax ID Number while the grantor is alive?
Usually no. The grantor’s Social Security number is used, and income is reported on the grantor’s personal return. Some banks may still request an EIN as a policy matter.
Do irrevocable trusts need a Trust Tax ID Number?
In most cases yes. The trust is treated as a separate taxpayer and must obtain its own EIN. Limited exceptions exist for certain grantor trusts.
How do I get a Trust Tax ID Number online for free?
Go to the official IRS EIN application page, select Trust as the entity type, complete the questions with accurate trust and responsible-party information, and receive the number immediately at the end of the session.
How long does it take to get a Trust Tax ID Number?
Online applications issue the number instantly. Fax takes about four business days. Mail takes approximately four weeks.
Can I open a trust bank account with a Trust Tax ID Number?
Yes. Provide the EIN confirmation, the trust document, and identification. The bank will title the account in the name of the trust using the EIN.
What happens if I keep using the grantor’s SSN after death?
Banks may refuse transactions, tax forms can mismatch IRS records, and you risk compliance issues. Obtain the new EIN promptly.
Is there a fee for the IRS free Trust Tax ID Number application?
No. The IRS does not charge for an EIN. Avoid third-party sites that add fees for the same service.