U.S. · Schedule 8812 line 18a
Schedule 8812 line 18a, earned income.
Which worksheet to use, and what lines 19 and 20 do with the number.
Schedule 8812 line 18a is your earned income. Taxpayers with self-employment income who use an optional method use the Earned Income Worksheet; everyone else uses the Earned Income Chart in the instructions, which points to your EIC figures if you take the earned income credit. Line 19 then subtracts $2,500 and line 20 takes 15% of the result.
Work out line 18a
Result
Reference table
| If you... | Enter on line 18a |
|---|---|
| Have net self-employment earnings and use an optional method | The Earned Income Worksheet amount, even if you also take the EIC. |
| Take the EIC and completed Worksheet B in the Form 1040 instructions | Line 4b of that worksheet plus nontaxable combat pay you did not elect to include. |
| Take the EIC without Worksheet B | Earned income from Step 5 of the EIC instructions plus nontaxable combat pay not already included. |
| Do not take the EIC | The Earned Income Worksheet amount. |
| Have tax-treaty income | It is excluded from earned income. |
| Are a bona fide Puerto Rico resident | Only earned income reported on Form 1040 or 1040-SR. |
Which method to use
The line 18a instructions say that if you have net earnings from self-employment and use either optional method to figure them, you use the Earned Income Worksheet. All other taxpayers can use the Earned Income Chart. Income excluded under a tax treaty is also excluded from the computation of earned income on line 18a.
What happens on lines 18b to 20
Line 18b is nontaxable combat pay (Form 1040 line 1i or Form W-2 box 12 code Q). On line 19, if line 18a is more than $2,500 you subtract $2,500; if not, line 19 stays blank and line 20 is -0-. Line 20 is 15% of line 19.
What line 20 is compared with
Line 17 is the smaller of line 16a and line 16b. If line 16b is $5,100 or more and line 20 is less than line 17, you also go to Part II-B. Otherwise the smaller of line 17 and line 20 is entered on line 27 as your additional child tax credit. Puerto Rico bona fide residents have a special route.
Worked example
Earned income of $30,000 gives line 19 of $27,500 and line 20 of $4,125 (15%). If line 17 is $1,700, the smaller of the two, $1,700, is the additional child tax credit before any Part II-B step. Figures are illustrative.
Limits of this page
The calculator starts from the earned income you already worked out. It does not compute the chart or the worksheet, which depend on your Form 1040, and it does not decide whether Part II-B applies to you. Filers of Form 2555 cannot claim the additional child tax credit.
Sources
- Instructions for Schedule 8812 (Form 1040) (2025): Line-by-line instructions, worksheets and limits. Read November 2, 2026.
- Schedule 8812 (Form 1040) (2025): The form itself, for exact line wording. Read November 2, 2026.
These are the tax year 2025 edition instructions and forms (published for returns filed in 2026). The IRS revises them each year, so thresholds, line numbers and limits can change; check the current edition before relying on a figure.
Frequently asked questions
What is line 18a on Schedule 8812?
Earned income, taken from the Earned Income Chart or the Earned Income Worksheet in the instructions.
What does line 19 do?
If line 18a is more than $2,500 it subtracts $2,500; otherwise line 19 is left blank and line 20 is -0-.
What percentage is used on line 20?
15% of the amount on line 19.
Does combat pay count?
Nontaxable combat pay is entered on line 18b and is part of the earned income figure only as the instructions describe.
Which tax year is this?
The 2025 edition of Schedule 8812 and its instructions.
Not tax or legal advice
This page summarizes IRS instructions and is not tax, legal or financial advice. A CPA, enrolled agent or the IRS can confirm what applies to your situation. Everything runs in your browser; nothing you enter is sent anywhere.