Schedule 1 (Form 1040) + AI Agent Skill: Additional Income Guide 2026

Hi, I'm Slava, CEO and co-founder of Jupid. Schedule 1 is the form most filers don't know they need until they need it — the moment a 1099-K shows up from Etsy, the year a side gig pays more than expected, the spring after a layoff turned into unemployment compensation. Working with small business owners through Anna Money and now Jupid, I see the same pattern: income makes it onto Schedule 1, but adjustments like student loan interest, self-employed health insurance, and SEP-IRA contributions get left behind. That's money walked away from.

Official IRS resources: Schedule 1 (Form 1040) (PDF) · Instructions (PDF) · About Schedule 1 (Form 1040)

Schedule 1 is the bridge between Form 1040 and the rest of your tax life. Anything that isn't W-2 wages, ordinary interest, dividends, or retirement distributions probably touches this schedule. Above-the-line deductions also live here.

This guide walks every line of Schedule 1 for tax year 2026, explains where each number comes from, and shows how the totals flow into Form 1040.

What Is Schedule 1?

Schedule 1 (officially "Additional Income and Adjustments to Income") is an attachment to Form 1040, 1040-SR, or 1040-NR. It has two jobs:

• Part I reports income that doesn't fit on the main Form 1040 income lines (wages, interest, dividends, retirement, Social Security, capital gains)
• Part II reports adjustments — also called "above-the-line deductions" — that reduce your gross income before the standard or itemized deduction is applied

The result of Part I (Line 10) flows to Form 1040 Line 8 (additional income). The result of Part II (Line 26) flows to Form 1040 Line 10 (adjustments). Together they shape your Adjusted Gross Income (AGI), which determines eligibility for many credits and phaseouts.

Legal basis: IRC §61 defines gross income broadly. IRC §62 lists the specific deductions allowed in computing AGI — these are the items that show up in Part II of Schedule 1.

Who Files Schedule 1?

You file Schedule 1 if:

• You received unemployment compensation
• You ran a side business or had self-employment income (Schedule C → Line 3)
• You had rental real estate, royalty, partnership, S-corp, or trust income (Schedule E → Line 5)
• You had farm income (Schedule F → Line 6)
• You received a state or local tax refund and itemized deductions in the prior year
• You received gambling winnings, jury duty pay, prizes, or hobby income
• You received digital assets (crypto, NFTs) as ordinary income
• You paid student loan interest, made HSA or SEP-IRA contributions, or paid self-employed health insurance premiums
• You paid alimony under a pre-2019 divorce decree (or received it under one)
• You owe self-employment tax — half of it is deductible on Line 15

You skip Schedule 1 if your only income is W-2 wages and standard interest/dividends, and you have no above-the-line adjustments.

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Executive Summary: Schedule 1 2026 Key Numbers

The form structure is fixed — Part I has Lines 1-10, Part II has Lines 11-26. The numeric limits attached to specific lines change year to year. Most 2026 figures will be announced by the IRS in October-December 2025; the table below uses 2025 values as a reference and flags every figure that needs verification before filing a 2026 return.

Critical 2026 caveats: Most inflation-adjusted figures on Schedule 1 are set by IRS Revenue Procedures issued the prior fall — verify each cap at irs.gov/forms-instructions before filing. Student loan interest is permanent at $2,500/year (IRC §221); only the income phaseout adjusts annually. Alimony rules depend on the divorce decree date — pre-2019 decrees use old rules (deductible/taxable); post-2018 decrees use TCJA rules (neither).

Legal basis: IRC §61, §62, §221, §223; IRS Publications 525 and 17.

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Part I — Additional Income (Line by Line)

Part I aggregates every income source that isn't on the main Form 1040 income lines.

Line 1 — Taxable Refunds, Credits, or Offsets of State and Local Income Taxes

A state or local income tax refund is taxable only if you itemized deductions in the prior year and got a tax benefit from deducting state income taxes. If you took the standard deduction last year, your refund is not taxable and doesn't go on Line 1. Most 2026 filers take the standard deduction, so Line 1 is often blank.

If you did itemize, use the worksheet in IRS Publication 525 and consider the SALT cap interaction — if your $10,000 SALT cap was already maxed by property tax, the state income tax deduction may not have produced a benefit.

Line 2a — Alimony Received

Alimony received under a divorce or separation agreement executed before January 1, 2019 is reported here. For agreements executed after December 31, 2018, alimony received is not taxable income and doesn't appear on Schedule 1 — TCJA repealed the income inclusion for post-2018 decrees.

Line 2b is a date field for the original decree.

Legal basis: IRC §71 (pre-TCJA rules, still apply to pre-2019 decrees).

Line 3 — Business Income or (Loss)

This is your net profit or loss from Schedule C. If you ran a sole proprietorship or single-member LLC, Schedule C Line 31 flows here. If Line 31 was a profit, Line 3 is positive; if a loss, Line 3 is negative (in parentheses).

For a complete walk-through of Schedule C, see our Schedule C Instructions Guide 2026.

Line 4 — Other Gains or (Losses)

From Form 4797 (sales of business property) or Form 4684 (casualties and thefts). Most solo filers leave this blank.

Line 5 — Rental Real Estate, Royalties, Partnerships, S Corporations, Trusts, Etc.

Net result from Schedule E. This includes:

• Residential rental property income/loss
• Royalty income from books, music, mineral rights, etc.
• Income from partnerships (K-1)
• Income from S corporations (K-1)
• Income from estates and trusts (K-1)

If you own a rental as a sole proprietor (not as a real estate dealer), the income belongs on Schedule E, not Schedule C — and Schedule E flows here.

Line 6 — Farm Income or (Loss)

From Schedule F. Farmers report on Schedule F instead of Schedule C; the net result lands on Line 6 of Schedule 1.

Line 7 — Unemployment Compensation

Total unemployment compensation received during the year, reported to you on Form 1099-G Box 1. State and federal unemployment benefits are both taxable at the federal level.

If you repaid a 2026 overpayment during the same year, check the box and enter the repayment amount.

Note: Pandemic-era exclusions (the $10,200 exclusion for 2020) are not in effect for 2026. All unemployment is taxable.

Line 8 — Other Income (8a through 8z)

Catchall for income types that don't fit Lines 1-7. The 2025 form (structuring the 2026 form) lists 22 sub-lines plus a "list type and amount" row at 8z. Common items for solo filers:

Gig workers and 1099-K recipients: If you received a 1099-K for trade or business activity (regular Etsy sales, rideshare, freelance gigs), that income belongs on Schedule C, not Line 8. Schedule C net profit flows to Schedule 1 Line 3.

If you received a 1099-K in error or for personal items sold at a loss (used furniture on Facebook Marketplace, concert tickets reimbursed via PayPal G&S), there's a special line at the top of Schedule 1 above Part I where you enter that amount so the IRS doesn't treat the entire 1099-K as taxable income.

Line 9 — Total Other Income

Add Lines 8a through 8z. Some lines (8a, 8d, 8s) are entered as negatives; the sum can therefore be negative.

Line 10 — Total Additional Income

Combine Lines 1-7 and Line 9. The result flows to Form 1040 Line 8.

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Part II — Adjustments to Income (Above-the-Line Deductions)

Part II is where above-the-line deductions live. These reduce Adjusted Gross Income whether or not you itemize. They are often more valuable than itemized deductions because lower AGI improves eligibility for credits and reduces phaseout impact.

Line 11 — Educator Expenses

Up to $300 (2025 figure; 2026 amount typically announced October 2025) for unreimbursed expenses by K-12 teachers, counselors, principals, and aides who worked at least 900 hours in a school year. Eligible expenses include books, supplies, computer equipment, and professional development.

Legal basis: IRC §62(a)(2)(D).

Line 12 — Reservists, Performing Artists, Fee-Basis Government Officials

Three narrow groups deduct unreimbursed business expenses above the line via Form 2106: Armed Forces reservists traveling 100+ miles for reserve duty; qualifying performing artists with 2+ employers and AGI under $16,000; state/local government officials paid on a fee basis. Most filers leave this blank.

Line 13 — Health Savings Account (HSA) Deduction

If you contributed to an HSA outside of payroll, the contribution deducts here via Form 8889. 2025 limits: $4,300 self-only, $8,550 family, $1,000 catch-up at 55+. 2026 figures were announced by the IRS in May 2025 — verify before filing.

You must be enrolled in a qualifying HDHP. Contributions deducted on payroll are already excluded from Box 1 W-2 wages and do not go here.

Legal basis: IRC §223; IRS Publication 969.

Line 14 — Moving Expenses for Members of the Armed Forces

Active-duty service members moving on permanent change of station orders deduct moving expenses on Form 3903 → Line 14. Civilians cannot deduct moving expenses (TCJA suspended this deduction; verify current status in IRS Publication 521).

Line 15 — Deductible Part of Self-Employment Tax

Half of the SE tax you owe (calculated on Schedule SE) deducts here — the "employer-equivalent" portion of FICA. Example: $80,000 Schedule C profit × 0.9235 × 0.153 = $11,304 SE tax; half = $5,652 on Line 15. Math: Schedule SE Line 13 → Schedule 1 Line 15. Legal basis: IRC §164(f).

Line 16 — Self-Employed SEP, SIMPLE, and Qualified Plans

Contributions to retirement plans for the self-employed: SEP-IRA (25% of net SE earnings after §164(f), capped at $70,000 for 2025; 2026 announced fall 2025); SIMPLE IRA (annual cap); Solo 401(k) (employer + employee for owner-employees). Contributions for employees go on Schedule C Line 19, not here.

Line 17 — Self-Employed Health Insurance Deduction

Health, dental, and qualified LTC premiums paid by a self-employed person for themselves, spouse, dependents, and children under 27. Limited to net Schedule C profit. Disqualifier: you cannot claim this if you or your spouse were eligible for an employer-subsidized plan during the same period.

For a deeper walk-through, see our Health Insurance Deduction Guide for Self-Employed 2026. Legal basis: IRC §162(l).

Line 18 — Penalty on Early Withdrawal of Savings

If you cashed out a CD or savings instrument before maturity and incurred an early withdrawal penalty, the penalty is deductible here. The bank reports it to you on Form 1099-INT Box 2.

Line 19a — Alimony Paid

Alimony paid under a pre-2019 divorce decree is deductible. Post-2018 decrees: no deduction, mirroring the no-inclusion rule for the recipient.

Lines 19b and 19c capture the recipient's SSN and original decree date.

Line 20 — IRA Deduction

Traditional IRA contributions, subject to deduction phase-outs based on whether you (or your spouse) are covered by an employer retirement plan. The phase-out income ranges adjust annually — verify 2026 figures via Rev. Proc. 2025-XX.

Roth IRA contributions are not deducted here (they're after-tax).

If you're married filing separately and lived apart from your spouse the entire year, check the box.

Line 21 — Student Loan Interest Deduction

Up to $2,500 of interest paid on qualified student loans, subject to MAGI phaseout (single $80,000-$95,000 in 2025; MFJ roughly double — verify 2026 ranges). Lender reports on Form 1098-E. Available even with standard deduction — one of the most-missed adjustments. Legal basis: IRC §221.

Line 22 — Reserved for Future Use

Currently blank. The IRS reserves line numbers for future legislative changes.

Line 23 — Archer MSA Deduction

Archer Medical Savings Accounts predate HSAs and are largely closed to new entrants. Contributions deduct via Form 8853. Most filers leave Line 23 blank — HSAs (Line 13) replaced this for new contributors.

Line 24 — Other Adjustments (24a through 24z)

Catchall for adjustments that don't fit Lines 11-23:

Line 25 — Total Other Adjustments

Sum of 24a through 24z.

Line 26 — Total Adjustments to Income

Add Lines 11 through 23 plus Line 25. The result flows to Form 1040 Line 10.

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How Schedule 1 Flows Into Form 1040

The two totals on Schedule 1 land in two specific places on Form 1040:

Schedule 1, Line 10  →  Form 1040, Line 8   (Additional income)
Schedule 1, Line 26  →  Form 1040, Line 10  (Adjustments to income)

Form 1040 then computes:

Line 9  = Wages + Interest + Dividends + Retirement + Capital gains + Schedule 1 Line 10
Line 11 = Line 9 − Schedule 1 Line 26  (Adjusted Gross Income)
Line 12 = Standard deduction OR itemized deductions (Schedule A)
Line 13 = QBI deduction (Form 8995 or 8995-A)
Line 15 = Taxable income  (Line 11 − Line 12 − Line 13)

The math chain matters because AGI (Line 11) is the gating number for many other things on the return — IRA deduction phaseouts, student loan interest phaseout, premium tax credit, retirement saver's credit, medical expense floor on Schedule A. Reducing AGI through Schedule 1 Part II adjustments is more valuable than the same dollar of itemized deduction.

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Worked Example: Maya the Freelance Designer with Side Gig Income

Maya runs a freelance graphic design business as a sole proprietor and sells digital prints on Etsy. Her 2026 numbers:

• Schedule C net profit (freelance + Etsy combined): $40,000 (gross $48,500 − $8,500 expenses)
• Student loan interest paid (Form 1098-E): $700
• Self-employed health insurance (marketplace ACA): $4,200
• SEP-IRA contribution: $1,500
• Half of self-employment tax (from Schedule SE): $2,826

Maya's Self-Employment Tax (preview)

Net SE earnings  = $40,000 × 0.9235        = $36,940
SE tax           = $36,940 × 0.153         = $5,652
Half of SE tax   = $5,652 / 2              = $2,826  → Line 15

Maya's Schedule 1

Part I — Additional Income
Line 1   State tax refund                 $0
Line 3   Schedule C net profit            $40,000
Line 4   Other gains                      $0
Line 5   Schedule E                       $0
Line 6   Schedule F                       $0
Line 7   Unemployment                     $0
Line 8   Other income (8a-8z)             $0
Line 9   Total other income               $0
Line 10  TOTAL ADDITIONAL INCOME          $40,000   →  Form 1040 Line 8

Part II — Adjustments to Income
Line 11  Educator expenses                $0
Line 13  HSA deduction                    $0
Line 14  Armed Forces moving              $0
Line 15  1/2 SE tax                       $2,826
Line 16  SEP-IRA contribution             $1,500
Line 17  SE health insurance              $4,200
Line 18  Early withdrawal penalty         $0
Line 19a Alimony paid                     $0
Line 20  IRA deduction                    $0
Line 21  Student loan interest            $700
Line 23  Archer MSA                       $0
Line 25  Total other adjustments (24)     $0
Line 26  TOTAL ADJUSTMENTS                $9,226    →  Form 1040 Line 10

How Maya's numbers flow into Form 1040

Assume Maya is single, no W-2 income.

Line 1z  Wages                                         $0
Line 8   Schedule 1 Line 10                            $40,000
Line 9   Total income                                  $40,000
Line 10  Schedule 1 Line 26                            $9,226
Line 11  Adjusted Gross Income (AGI)                   $30,774
Line 12  Standard deduction (2026 single — verify)     $15,700 (estimate)
Line 13  QBI deduction (20% × QBI, simplified)         $3,073
Line 15  Taxable income                                $12,001

Federal income tax on $12,001 (single) lands in the 10-12% brackets — roughly $1,200. Plus the full $5,652 SE tax (the half-deducted on Line 15 only reduces income tax, not SE tax). Total federal: about $6,852.

Without the $9,226 in adjustments, AGI would have been $40,000 — higher bracket, smaller QBI deduction. The four adjustments saved Maya roughly $1,100-$1,400 in income tax plus ripple effects on credits.

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Common Mistakes to Avoid

Mistake #1: Reporting Hobby Income With Expense Offsets

Problem: A filer with $5,000 hobby income on Line 8j deducts $4,000 of hobby expenses to net $1,000.

Impact: Under TCJA, hobby expenses are not deductible. Netting understates taxable income and triggers an IRS adjustment.

Solution: Report gross hobby income on Line 8j. If the activity is regular and for-profit, it's a trade or business — file Schedule C instead.

Mistake #2: Forgetting the Student Loan Interest Deduction

Problem: A filer with $1,800 of student loan interest takes the standard deduction and skips Line 21, assuming "I didn't itemize so I can't deduct anything."

Impact: $1,800 deduction missed → ~$396 of tax overpayment at the 22% bracket.

Solution: Line 21 is above-the-line — available regardless of standard vs. itemized. If MAGI is below the phaseout ceiling, claim it.

Mistake #3: Missing Self-Employed Health Insurance Deduction

Problem: A self-employed filer paid $6,000 in marketplace ACA premiums but didn't put it on Line 17 because "I deducted it on Schedule C."

Impact: Owner health insurance doesn't belong on Schedule C. If also wrongly added to Schedule C, that's a second error (overstated business expense).

Solution: Owner health insurance goes on Schedule 1 Line 17, not Schedule C Line 14 (Line 14 is for employee benefits). Limited to net Schedule C profit. See our Health Insurance Deduction Guide 2026.

Mistake #4: Double-Counting Schedule C Profit

Problem: A filer reports Schedule C net profit of $50,000 on Line 3, and separately adds $50,000 of "self-employment income" on Line 8z.

Impact: $50,000 of phantom income, $7,650 phantom SE tax.

Solution: Schedule C net profit goes on Line 3 only. Schedule SE is a parallel calculation, not duplicate income.

Mistake #5: Reporting State Refund as Taxable When It Shouldn't Be

Problem: A filer who took the standard deduction in 2025 reports a $400 state refund on Line 1 in 2026.

Impact: $400 phantom income, ~$88 unnecessary tax at 22% bracket.

Solution: A state refund is taxable on Line 1 only if you itemized last year and got a tax benefit from deducting state income tax. If you took the standard deduction, leave Line 1 blank.

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How Jupid AI Helps with Schedule 1

Schedule 1 is where the most adjustments get missed. Filers know Schedule C and Schedule SE because they're loud. Schedule 1 adjustments — student loan interest, SEP-IRA contributions, SE health insurance — sit quietly and get forgotten when filers rush through software.

What Jupid does for Schedule 1:

• Bank-connected categorization — The 1098-E from your servicer, marketplace ACA premium charges, and SEP-IRA transfers all land in your transaction stream automatically. Jupid tags each as a Schedule 1 adjustment.
• 95.9% transaction categorization accuracy — Every business expense routes to the right Schedule C line, so when Schedule C net profit feeds Schedule 1 Line 3, the number is defensible.
• AI accountant in WhatsApp/iMessage — Ask "Did I claim my student loan interest this year?" — Jupid pulls the answer from your real transactions.
• Auto-filing — Jupid maps Schedule C Line 31 → Schedule 1 Line 3, half of Schedule SE → Line 15, HSA contributions → Line 13, student loan interest → Line 21, SE health insurance → Line 17.

Example conversation:

• You: "What goes on Schedule 1 for me this year?"
• Jupid: "Schedule C net profit $42,300 → Line 3. Half of $5,977 SE tax → $2,988 on Line 15. SEP-IRA $2,000 → Line 16. Marketplace ACA premiums $5,400 → Line 17. Student loan interest $1,247 → Line 21. Total adjustments: $11,635."

Try Jupid →

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Action Checklist: Filing Schedule 1

Before Tax Time

• Save every 1099: 1099-NEC, 1099-K, 1099-G, 1099-MISC, 1098-E
• Track HSA and SEP-IRA contributions made during the year
• Keep marketplace health insurance Form 1095-A
• Note any state tax refund (Form 1099-G Box 2)

Throughout the Year

• Categorize self-employment income as it comes in (feeds Line 3)
• Track prizes, gambling winnings, jury duty, hobby income
• Track digital asset receipts (crypto, NFT, staking) — Line 8v
• Pay quarterly estimated taxes if Schedule C profit ≥ $5,000

At Tax Time

• Verify 2026 inflation-adjusted figures against latest IRS Revenue Procedure
• Complete Schedule C and Schedule SE before Schedule 1 (feed Lines 3 and 15)
• Complete Form 8889 if HSA contributions made outside payroll → Line 13
• Cross-check Line 10 → Form 1040 Line 8 and Line 26 → Form 1040 Line 10

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Resources and Citations

IRS Forms and Instructions

• Schedule 1 (Form 1040) — Additional Income and Adjustments to Income
• Form 1040 Instructions — General instructions covering Schedule 1 line by line
• About Schedule 1 — IRS landing page with current and prior-year revisions
• Form 8889 — Health Savings Accounts (HSAs)
• Form 1098-E — Student Loan Interest Statement

IRS Publications

• Publication 17 — Your Federal Income Tax (For Individuals)
• Publication 525 — Taxable and Nontaxable Income
• Publication 521 — Moving Expenses (current rules for Armed Forces)
• Publication 535 — Business Expenses
• Publication 969 — Health Savings Accounts and Other Tax-Favored Health Plans
• Publication 970 — Tax Benefits for Education (covers student loan interest)

Tax Code References

• IRC §61 — Definition of gross income
• IRC §62 — Adjusted gross income (above-the-line deductions list)
• IRC §71 — Alimony (pre-2019 decrees)
• IRC §162(l) — Self-employed health insurance deduction
• IRC §164(f) — Half of self-employment tax deduction
• IRC §221 — Student loan interest deduction
• IRC §223 — Health Savings Account contributions
• IRC §274(n) — 50% meal deduction limit (for the Schedule C side, referenced when computing Line 3)

Year-Specific Authority

• Rev. Proc. 2024-25 — 2025 HSA contribution limits
• Rev. Proc. 2024-40 — 2025 inflation adjustments (educator, student loan phaseout)
• Notice 2024-80 — 2025 retirement plan contribution limits
• Rev. Proc. 2025-XX — 2026 inflation adjustments (verify before filing)

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Final Thoughts

Schedule 1 is where Form 1040 stops being a single page and starts being the real return. Part I gets reported because the IRS already has matching 1099s, but Part II gets skipped because nobody reminds filers about above-the-line adjustments. The four adjustments solo filers miss most often — half of SE tax (Line 15), SE health insurance (Line 17), SEP-IRA contributions (Line 16), and student loan interest (Line 21) — routinely shave $5,000-$15,000 off AGI for a mid-five-figure freelancer.

Key strategies:

1. Treat Schedule 1 as required — every solo filer with self-employment income files it.
2. Verify 2026 inflation-adjusted figures before filing — announced October-December 2025 in IRS Revenue Procedures.
3. Map every 1099 to a Schedule 1 line first — 1099-G unemployment → Line 7; 1099-G state refund → Line 1 (if itemized prior year); 1099-MISC prize → Line 8i; 1099-NEC business → Schedule C → Line 3.
4. Run the AGI math both ways — with and without Part II adjustments.

Use This with Your AI Agent

If you're using Claude, ChatGPT, or another AI agent to help fill out Schedule 1 (Form 1040), we've published an open-source skill that gives the agent exact line-by-line instructions, validation checks, ask-don't-guess prompts, and worked examples — the same logic Jupid uses internally.

→ jupid-tax/jupid-skills on GitHub — forms/schedule-1/

For Claude Code: cp -r jupid-skills/forms/schedule-1 ~/.claude/skills/. For the Anthropic SDK, load SKILL.md into the system prompt and the references/ files on demand. For browser-automation runtimes, filing.md covers the e-file or paper-file workflow.

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Disclaimer

This article provides general information about Schedule 1 of Form 1040 and should not be considered tax advice. Tax laws change frequently, individual circumstances vary, and inflation-adjusted figures for tax year 2026 are subject to verification against the latest IRS Revenue Procedures. For advice specific to your situation, consult with a qualified tax professional.

Tax Year: 2026 (forms covering tax year 2026 income, filed in 2027) Last Updated: April 27, 2026