Updated October 18, 2026. Quick answer: Schedule SE is the form that figures self-employment tax on your net earnings from self-employment. Part I is the tax itself, on lines 1 to 13, and Part II holds the optional methods, on lines 14 to 17. Most sole proprietors get the starting number from the profit on Schedule C (Form 1040), and the finished tax carries to Schedule 2 and then to Form 1040.
Picking the Schedule C business code for your work (2025 chart): Schedule C code for Etsy sellers and Schedule C code for doctors and dentists.
Picking the Schedule C business code for your work (2025 chart): Schedule C business codes and Schedule C code for landscapers.
Related reading on this site: IRS Publication 334.
Form lines read one part at a time: Form 8959 Part II.
IRS worksheets read line by line: EIC Worksheet B.
What Schedule SE does
The instructions open with the purpose of the form: “Use Schedule SE (Form 1040) to figure the tax due on net earnings from” self-employment. They add that the Social Security Administration uses the schedule to figure your benefits, and that “This tax applies no matter how old you are and even if you are already getting social security or Medicare benefits.”
This page is the overview. The two line pages cover the form in order: Schedule SE lines 1 to 4 builds your net earnings, and Schedule SE lines 5 to 13 applies the social security base and works out the tax. The profit that usually feeds line 2 comes from Schedule C (Form 1040), and self-employment tax explained gives the wider background.
Who must file Schedule SE
The instructions give two tests. You must file Schedule SE if “The amount on line 4c of Schedule SE is $400 or more, or” if you “had church employee income of $108.28 or more”. There is an exception for people with IRS approval: “If you filed Form 4029 or Form 4361 and received IRS approval, you may not need to file Schedule SE.”
A loss does not always mean skipping the form. The instructions say “it may be to your benefit to file Schedule SE” when you had a loss or a small amount of self-employment income and could use an optional method.
Who pays self-employment tax
For people in business for themselves the rule is short: “pay SE tax if you had net earnings of $400 or more as a” self-employed person. “If you are in business (farm or nonfarm) for yourself, you are” self-employed. The instructions also list other groups with their own rules, including church employees, ministers, partners and people living outside the United States, so read the matching heading in the instructions if one of those describes you.
If you have more than one business, the instructions say to combine them: “Figure the combined SE tax on one Schedule SE.” On a joint return, “If both spouses have” self-employment income, “each must file a separate Schedule SE.”
The parts of the form
Schedule SE has two parts. The form heads the first one “Self-Employment Tax” and the second “Optional Methods To Figure Net Earnings (see instructions)”. The table maps the lines to the two line pages on this site.
| Lines | What they do | Where to read about it |
|---|---|---|
| Lines 1a, 1b, 2, 3 | Net farm profit, Conservation Reserve Program payments, net profit from Schedule C, and the combined total | Schedule SE lines 1 to 4 |
| Lines 4a to 4c | The 92.35% multiplication and the $400 test | Schedule SE lines 1 to 4 |
| Lines 5a to 6 | Church employee income and the total subject to the tax | Schedule SE lines 5 to 13 |
| Lines 7 to 11 | The social security base, W-2 wages already taxed, and the two tax rates | Schedule SE lines 5 to 13 |
| Lines 12 and 13 | The self-employment tax and the one-half deduction | Schedule SE lines 5 to 13 |
| Lines 14 to 17 (Part II) | Optional methods, described below | Instructions for Part II |
Optional methods in Part II
Part II is for a smaller group of filers. The instructions explain the idea: “The optional methods may give you credit toward your social security coverage even though you have a loss or a small amount of income from” self-employment. They also caution that “Using the optional methods as described above may be beneficial, but they may also increase your SE tax.” Because the eligibility tests and the farm and nonfarm limits are set out in the instructions for Part II, work through those instructions before using lines 14 to 17.
Where the totals go
Line 12 is the tax itself. The form says to “Add lines 10 and 11. Enter here and on Schedule 2 (Form 1040), line 4”. That figure is explained on the Schedule 2 line 4 page and then flows to Form 1040. Line 13 is the one-half deduction, and the form says to “Multiply line 12 by 50% (0.50). Enter here and on Schedule 1 (Form 1040), line 15”. See Schedule 1 lines 15 and 16 for how that deduction is used.
Edition and line numbers
This page reads the 2025 Schedule SE (Form 1040) and its 2025 instructions, the current files irs.gov served on 2026-10-18 (byte-identical to the archived copies). They are the files for the tax year 2025 return, filed in 2026. The schedule says “Attach to Form 1040, 1040-SR, 1040-SS, or 1040-NR.” Check the tax year printed on the schedule you are filling in and use the line numbers on that year’s schedule, because a different year’s schedule can number or word its lines differently.
Common mistakes
- Believing the tax stops at a certain age or once benefits start. The instructions say “This tax applies no matter how old you are and even if you are already getting social security or Medicare benefits.”
- Skipping the schedule because the business lost money. The instructions say “it may be to your benefit to file Schedule SE” in that case, so check the optional methods first.
- Putting both spouses on one schedule. The instructions say “each must file a separate Schedule SE.”
Related: Schedule C (Form 1040), Schedule 2 line 4, self-employment tax explained, Schedule 1 lines 15 and 16, and Form 1040.
Sources
- Instructions for Schedule SE (Form 1040), Self-Employment Tax (2025): https://www.irs.gov/pub/irs-pdf/i1040sse.pdf
- Schedule SE (Form 1040), Self-Employment Tax (2025): https://www.irs.gov/pub/irs-pdf/f1040sse.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.