U.S. · Tax forms
Form 1040 line 24, total tax.
How lines 16 through 23 build up to the total, and why the number matters later.
Line 24 reads “Add lines 22 and 23. This is your total tax.” Line 22 is your tax after nonrefundable credits, and line 23 is other taxes, including self-employment tax, from Schedule 2, line 21.
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Result
Form 1040 Line 24 at a glance, 2025 edition
| Line | Label on the 2025 form | How it builds to line 24 |
|---|---|---|
| Line 16 | Tax (see instructions) | Income tax on taxable income |
| Line 17 | Amount from Schedule 2, line 3 | Adds to line 16 |
| Line 18 | Add lines 16 and 17 | Tax before credits |
| Line 19 | Child tax credit or credit for other dependents from Schedule 8812 | Part of line 21 |
| Line 20 | Amount from Schedule 3, line 8 | Part of line 21 |
| Line 21 | Add lines 19 and 20 | Subtracted from line 18 |
| Line 22 | Subtract line 21 from line 18. If zero or less, enter -0- | First half of line 24 |
| Line 23 | Other taxes, including self-employment tax, from Schedule 2, line 21 | Second half of line 24 |
| Line 24 | Add lines 22 and 23. This is your total tax | The result |
Reading the chain
Line 18 is tax before credits (lines 16 and 17). Lines 19 and 20 are the credits; line 21 totals them and line 22 subtracts them from line 18, never going below zero. Line 23 then adds the other taxes from Schedule 2 (such as self-employment tax). Line 24 is the sum.
Where line 24 is used
Line 33 adds your payments, and line 34 says that if line 33 is more than line 24, the difference is the amount you overpaid. If line 24 is larger, the difference is what you owe. The estimated tax penalty instructions also start from line 24: for most people the “tax shown on your return” is line 24 minus certain amounts, including those on lines 27a, 28, 29 and 30.
Worked example
Omar has line 16 tax of $5,200 and nothing on line 17, so line 18 is $5,200. He has a $2,000 child tax credit (line 19) and $300 of Schedule 3 credits (line 20), so line 21 is $2,300 and line 22 is $2,900. Schedule 2 line 21 is $1,400 of self-employment tax, so line 23 is $1,400. Line 24 is 2,900 + 1,400 = $4,300. Names and amounts are made up.
Limits
Line 24 is a total, not a bill. Payments and refundable credits on lines 25 through 33 decide whether you owe or are due a refund.
More line pages in this set
Related lines: Form 1040 Line 16, Form 1040 Line 15.
Sources
- Instructions for Form 1040 and 1040-SR (2025): Page last reviewed or updated May 7, 2026. Read November 2, 2026.
- Form 1040 (2025) Read November 2, 2026.
- Schedule 2 (Form 1040) 2025 Read November 2, 2026.
Tax year 2025 forms and instructions (Instructions for Form 1040 page last reviewed or updated May 7, 2026). Line labels were read from the IRS form PDFs posted on the date read; line numbers and labels change between tax years, so check them against the form for your tax year. Names in worked examples are made up.
Frequently asked questions
What is Form 1040 line 24?
It is your total tax: line 22 (tax after nonrefundable credits) plus line 23 (other taxes, including self-employment tax, from Schedule 2).
Why can line 22 not be negative?
The form says to enter -0- if line 21 is greater than line 18, so credits on lines 19 and 20 cannot reduce line 22 below zero.
Where does the line 23 amount come from?
From Schedule 2, line 21. Schedule 2 Part II includes self-employment tax on its line 4.
How does line 24 compare with payments?
If line 33 (total payments) is more than line 24, the difference is the amount you overpaid; otherwise you owe the difference.
Is line 24 used for the estimated tax penalty?
The instructions start from line 24 when defining the tax shown on your return, then subtract certain credits and amounts.
Not tax advice
This page summarizes IRS instructions, mostly written for the people who prepare the form, and is not tax, legal or financial advice. A CPA or an enrolled agent can confirm what a line means for your return. Everything runs in your browser; nothing you enter is sent anywhere.