When the grantor of a revocable living trust dies, the responsible party for the trust’s new EIN is the successor trustee named in the trust document. That person applies to the IRS using their own Social Security Number (or ITIN), and from that point forward they are the individual the IRS looks to for the trust’s tax filings, correspondence, and account access. Getting this right at the outset matters, because the successor trustee’s personal taxpayer ID is tied to the application and the filing obligations that follow.
Why the Trust Needs a New EIN at Death
While the grantor was alive, a revocable living trust used the grantor’s personal SSN for all tax reporting. At the moment of death, the trust becomes irrevocable by operation of law. It is now a separate taxable entity and needs its own EIN. The successor trustee should apply promptly, because the trust will need the number to open new bank accounts, receive income, and file its own Form 1041.
Two boundary points are worth knowing. If the trust was already irrevocable before the grantor’s death, it should already have an EIN and no new number is needed. And if the trust instrument directs that assets split into separate sub-trusts at death, each sub-trust is its own taxpayer and needs its own EIN.
The IRS limits EIN issuances to one per responsible party per day, applied per grantor for trusts. If the same grantor set up multiple trusts that all need new numbers at death, the successor trustee has to spread the applications across consecutive days.
What “Responsible Party” Means
The IRS defines the responsible party as the living individual who ultimately controls the entity and has the practical ability to direct its funds and assets. It must be a person, not an organization. For a trust, the IRS generally identifies that individual as the “grantor, owner, or trustor.” Once the grantor has died, they can no longer fill the role, so the successor trustee steps in, because they are now the person who controls the trust assets and directs their distribution. The successor trustee’s name and SSN or ITIN go on the EIN application.
When Co-Trustees Are Named
Only one individual can be listed as the responsible party on the application. Co-trustees should decide among themselves who that will be, keeping in mind that the IRS will send correspondence to the address associated with the person listed. The others still serve as trustees under the trust document; they simply are not the point of contact for the EIN.
Successor Trustees Who Aren’t U.S. Residents
A responsible party who is not a U.S. citizen and lacks an SSN enters their ITIN on line 7b of Form SS-4. If the person has neither an SSN nor an ITIN and isn’t eligible for one, the IRS instructions direct them to enter “foreign” or “N/A” on that line.
International applicants who have no legal residence, business, or agency in the United States cannot use the online EIN tool. They apply by calling the IRS at 267-941-1099 (not toll-free), Monday through Friday between 6:00 a.m. and 11:00 p.m. Eastern time. The caller must be authorized to receive the EIN and to answer questions about the application.
Filling Out Form SS-4 for the Trust
The application is IRS Form SS-4. A few lines are where trustees most often go wrong:
- Line 1: the full legal name of the trust, exactly as it appears in the trust document.
- Line 3: the name of the trustee serving as fiduciary.
- Lines 7a and 7b: the full name and SSN or ITIN of the responsible party (the successor trustee).
- Line 9a: select “Created a trust” for a trust that became irrevocable at death. Choosing the wrong entity type is one of the most common errors and will delay processing.
You will also need the date the trust was originally created, not the date of death.
How to Submit the Application
The fastest route is the IRS online EIN assistant, which issues the number immediately once the application validates. The tool is available Monday through Friday from 6:00 a.m. to 1:00 a.m. Eastern time, Saturdays from 6:00 a.m. to 9:00 p.m., and Sundays from 6:00 p.m. to midnight.
Applicants with a legal residence in any U.S. state or Washington, D.C. can fax Form SS-4 to 855-641-6935 and typically receive an EIN within four business days. Applicants in U.S. territories or abroad use 855-215-1627.
Mailing is the slowest option. The signed and dated form goes to Internal Revenue Service, Attn: EIN Operation, Cincinnati, OH 45999. Processing takes roughly four weeks.
What the Responsible Party Owes After the EIN Is Issued
The EIN is the start of the job, not the end of it. The trust must file Form 1041 for each year it has $600 or more in gross income. For a calendar-year filer, the return is due April 15 of the following year.
Missing the deadline triggers a penalty of 5% of the unpaid tax for each month (or part of a month) the return is late, capped at 25%. If the return is more than 60 days late, the minimum penalty is $525 or the total tax due, whichever is less. Interest runs on unpaid tax and penalties from the original due date, even where a filing extension was granted.
When the Responsible Party Changes Later
Successor trustees can resign, be replaced, or hand off primary duties to a co-trustee. When the responsible party changes, the trust must report the change to the IRS within 60 days using Form 8822-B. The form asks for the trust’s EIN, any new mailing address, and the new responsible party’s name and SSN or ITIN. The new trustee signs it. Processing typically runs four to six weeks.
There is no direct penalty for skipping Form 8822-B, but the practical consequence is worse than a fine. If the IRS can’t reach the current trustee, deficiency notices and demands for payment go to the wrong address while penalties and interest keep accruing. By the time the right person learns about a problem, the balance can be substantially larger than what was originally owed.