Updated October 18, 2026. Quick answer: Lines 18 to 30 finish Part III of Form 4972, the 10-year tax option. They subtract any federal estate tax, take 10% of the result, look up a tax on it in the schedule printed in the instructions, multiply that tax by 10.0, and add the Part II tax on line 30. Line 30 goes to Form 1040 line 16 with box 2 checked, or to Form 1041 Schedule G.
What this part is for
These are the closing lines of Part III. The instructions describe the option: “You can use Part III to figure your tax on the” lump-sum distribution using the 10-year tax option, and it is available “whether or not you make the 20% capital gain election.” The first half of Part III is at Form 4972 lines 8 to 17, and the whole form is mapped on the Form 4972 page.
The lines, one by one
| Line | What the form says |
|---|---|
| Line 18 | “Federal estate tax attributable to” lump-sum distribution. The instructions add that you “get this amount from the administrator of the deceased’s estate”. |
| Line 19 | “Subtract line 18 from line 17.” “If line 11 is zero, skip lines 20 through 22 and go to line 23” |
| Line 20 | “Divide line 11 by line 12 and enter the result as a decimal (rounded to at least three places)” |
| Line 21 | “Multiply line 16 by the decimal on line 20” |
| Line 22 | “Subtract line 21 from line 11” |
| Line 23 | “Multiply line 19 by 10% (0.10)” |
| Line 24 | “Tax on amount on line 23. Use the Tax Rate Schedule in the instructions” |
| Line 25 | “Multiply line 24 by 10.0.” “If line 11 is zero, skip lines 26 through 28, enter this amount on line 29, and go to line 30” |
| Line 26 | “Multiply line 22 by 10% (0.10)” |
| Line 27 | “Tax on amount on line 26. Use the Tax Rate Schedule in the instructions” |
| Line 28 | “Multiply line 27 by 10.0” |
| Line 29 | “Subtract line 28 from line 25.” “Multiple recipients, see instructions” |
| Line 30 | “Add lines 7 and 29.” “Also, include this amount in the total on Form 1040, 1040-SR, or 1040-NR, line 16 (check box 2), or Form 1041, Schedule G, line 1b” |
Lines 24 and 27 both say to use the Tax Rate Schedule in the instructions. That schedule is printed in the instructions to your own form and is not reproduced here. The instructions point to it with “Use the following Tax Rate Schedule to complete lines 24 and 27.”
Where the number comes from
Line 18 is the estate-tax line. The instructions say “get this amount from the administrator of the deceased’s estate”. Line 17 comes from the lines before it (see Form 4972 lines 8 to 17), line 11 from Form 1099-R box 8, and line 7 from Form 4972 Part II, lines 6 and 7.
For shared distributions, the instructions give a path through the lines: “Complete Form 4972 through line 28.” “Complete the following worksheet to figure the entry for Form 4972, line 29.” See Form 1099-R boxes 9a and 9b for the percentage boxes. For trusts the instructions say “If you are filing for a trust that shared the distribution only with other trusts, figure the tax on the total lump sum first.” “The trusts then share the tax in the same proportion that they shared the distribution.”
Where it goes next
Line 30 gives the destination: “Also, include this amount in the total on Form 1040, 1040-SR, or 1040-NR, line 16 (check box 2), or Form 1041, Schedule G, line 1b”. See Form 1040 line 16 on Form 1040, and Form 1041 Schedule G for an estate or trust (Form 1041 for estates).
A short illustration of lines 19 to 23
Illustration, not an IRS example. Every input is invented. This covers lines 19 to 23 only, because line 24 needs the schedule. Suppose line 17 is 34,000, line 18 is 0 and line 11 is 0.
| Item | Illustration |
|---|---|
| Line 17 (suppose, carried from the earlier lines; the results below are computed from it) | $34,000 |
| Line 18 (suppose no federal estate tax) | $0 |
| Line 11 (suppose Form 1099-R box 8 is blank, so line 11 is zero) | $0 |
| Line 19: line 17 minus line 18 | $34,000 (computed) |
| Line 23: 0.10 x line 19 | $3,400 (computed) |
Line 19 is 34,000 minus 0 = 34,000. Because line 11 is zero, the form says to skip lines 20 through 22, and line 23 is 0.10 x 34,000 = 3,400. Line 24 would then come from the Tax Rate Schedule in the instructions to your own form.
Edition and line numbers
This page reads Form 4972 for 2025 and its instructions, the current file irs.gov served on 2026-10-18, for a distribution received in 2025. Check the edition printed on your own form and use that edition’s line numbers.
Common mistakes
- Estimating the tax on lines 24 and 27 instead of looking it up. Both lines say “Use the Tax Rate Schedule in the instructions”
- Working lines 20 to 22 when line 11 is zero. Line 19 says “If line 11 is zero, skip lines 20 through 22 and go to line 23”
- Forgetting box 2 on the return. Line 30 says “Also, include this amount in the total on Form 1040, 1040-SR, or 1040-NR, line 16 (check box 2)”
Related: Form 1040 line 16, Form 1041 Schedule G, Form 1041 for estates, Form 1099-R box 8, and Form 1099-R boxes 9a and 9b.
Sources
- Form 4972 (2025) with instructions, Tax on Lump-Sum Distributions: https://www.irs.gov/pub/irs-pdf/f4972.pdf
- IRS: About Form 4972: https://www.irs.gov/forms-pubs/about-form-4972
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.