Updated October 18, 2026. Quick answer: Lines 3 to 5 of Form 56 say which taxes and which federal forms your fiduciary role covers, and for which years or periods. Check the boxes for the returns you will actually file, and use line 5 only when your authority is limited. The entries come from your list of returns to file.
What Section B asks
The part is titled “Nature of Liability and Tax Notices”. The instructions say “Check the appropriate box(es) indicating the type of tax and forms you will be filing in performance of your fiduciary duties.” Authority is entered earlier, on the Form 56 Part I page.
Line 3: type of taxes
The form says “Type of taxes (check all that apply)”. The list runs from income and gift to estate, “Generation-skipping transfer”, employment and excise, plus an other box to describe. For an estate, the choices follow the returns on the Form 706 and Form 709 pages.
Line 4: federal tax form number
The form says “Federal tax form number (check all that apply)”. The boxes include the “706 series” and the “709 series”, and the box for “1040 or 1040-SR”. An open box follows: “Other (list):” The estate’s income tax return is covered on the Form 1041 for estates page, and the decedent’s final income tax return on the final tax return for a deceased person page.
Line 5: all years or only some
The form says “If your authority as a fiduciary does not cover all years or tax periods, check here”. The instructions repeat it: “If your authority does not cover all years or tax periods, check the box on line 5a and list the specific years or periods within your authority on line 5b.” The form’s second line is “If you checked line 5a, list the specific years or periods within your authority:”
What to enter and where it comes from
Lines 3 and 4 come from your own plan: the returns you expect to file for the person you are acting for. Line 5 comes from the document that gave you authority, such as the court order or trust instrument described on the Form 56 Part I page. The instructions add a limit on what the form does: “Form 56 cannot be used to request copies of notices and correspondence.”
Where it goes next
These lines travel with the rest of the form. The form is filed as the instructions describe: “File Form 56 with the Internal Revenue Service Center where the person for whom you’re acting is required to file tax returns.” Revoking or replacing a fiduciary is on the Form 56 Part II page, and the signature and filing rules are on the Form 56 Parts III and IV page.
Edition and line numbers
This page reads Form 56 and the Instructions for Form 56, both revision dated June 2026. Each prints its own caption: the form shows “(Rev. June 2026)” and the instructions show “(Rev. June 2026)”. Those are the current files irs.gov served on 2026-10-18. Check the revision date printed on your own Form 56 and use that revision’s line numbers, because a different revision can number or word its lines differently. The form points to “Go to www.irs.gov/Form56 for instructions and the latest information.”
Common mistakes
- Checking boxes for returns you do not expect to file. The instructions say to check “the type of tax and forms you will be filing in performance of your fiduciary duties.”
- Leaving line 5 blank when authority is limited. The instructions say “check the box on line 5a and list the specific years or periods within your authority on line 5b.”
- Using Form 56 to ask for IRS letters. The instructions say “Form 56 cannot be used to request copies of notices and correspondence.”
Related: Form 56, Form 706, Form 709 who must file, Form 1041 for estates, and final tax return for a deceased person.
Sources
- Form 56, Notice Concerning Fiduciary Relationship (Rev. June 2026): https://www.irs.gov/pub/irs-pdf/f56.pdf
- Instructions for Form 56 (Rev. June 2026): https://www.irs.gov/pub/irs-pdf/i56.pdf
Read from the IRS documents linked above on October 18, 2026. General information, not tax advice. Your own facts decide the outcome, and a preparer, the account provider or the IRS is the right place to confirm anything consequential.