Simulators · Tax Year 2025

Scope & Assumptions

What each simulator includes, leaves out and assumes, form by form. The same notes appear inside the labs.

Across the Whole Lab

General Assumptions

  • The estimated tax penalty (Form 2210) and the premium tax credit (Form 8962) are not calculated.
  • State and local returns are not included.
  • All people and amounts are fictional; the lab does not prepare or file real returns.
  • Figures follow the 2025 IRS forms and the 2025 inflation adjustments, as amended by the 2025 tax law changes.
US Tax Training · Individual Tax

Form 1040 Lab: Forms, Schedules and Worksheets

Form 1040U.S. Individual Income Tax Return

Included

  • All income lines fed by the lab's documents: wages, interest, dividends, IRA and pension distributions, Social Security, capital gains and Schedule 1 income
  • Tax from the IRS Tax Table under $100,000 and the Tax Computation Worksheet above it, or the capital gain worksheet when there are qualified dividends or net capital gain
  • Credits and payments on lines 19–33, with the refund or amount owed

Not Included

  • Lines 1b–1i (household wages, unreported tips, Medicaid waiver payments, dependent care and adoption benefits, Form 8919 wages, combat pay)
  • Line 30 refundable adoption credit and line 38 estimated tax penalty (Form 2210)
  • Kiddie tax (Form 8615), lump-sum distributions (Form 4972) and state returns

Assumed

  • Every line is rounded to whole dollars
  • The taxpayer lived in the U.S. all year and had no digital asset transactions
  • Dependents have SSNs and meet the relationship, residency and support tests

Schedule 1Additional Income and Adjustments to Income

Included

  • Line 3 business income, line 5 Schedule E income, line 7 unemployment
  • Adjustments: educator expenses, HSA, deductible half of SE tax, early withdrawal penalty, IRA deduction and student loan interest

Not Included

  • State tax refunds, alimony, Form 4797 gains, farm income, net operating losses and other income on lines 8a–8z
  • Self-employed health insurance, SEP/SIMPLE contributions, Archer MSA and other adjustments on lines 24a–24z

Assumed

  • HSA contributions entered are personal contributions, not made through payroll
  • IRA contributions are to a traditional IRA for 2025
  • The IRA deduction phase-out uses modified AGI before taxable Social Security (the Pub. 590-A interaction is simplified)

Schedule 2Additional Taxes

Included

  • Alternative minimum tax (Form 6251)
  • Self-employment tax, the 10% additional tax on early distributions (Form 5329), Additional Medicare Tax (Form 8959) and net investment income tax (Form 8960)

Not Included

  • Repayment of excess advance premium tax credit (the premium tax credit is not calculated)
  • Household employment taxes, uncollected Social Security and Medicare tax, recapture taxes and section 965 installments

Assumed

  • Early distributions with code 1 have no exception to the 10% tax

Schedule 3Additional Credits and Payments

Included

  • Foreign tax credit, child and dependent care credit, education credits and the saver's credit

Not Included

  • Energy, clean vehicle, general business, adoption and elderly credits
  • Premium tax credit (Form 8962), extension payments, excess Social Security withholding and fuel tax credit

Assumed

  • Nonrefundable credits are applied in Schedule 3 order, then the child tax credit, each limited by the tax left

Schedule 1-AAdditional Deductions (new for 2025)

Included

  • No tax on tips (up to $25,000), qualified overtime (up to $12,500; $25,000 joint), new-car loan interest (up to $10,000) and the $6,000 senior deduction, each with its phase-out

Not Included

  • Add-backs for Puerto Rico and foreign income exclusions (lines 2a–2d are zero)

Assumed

  • Tips are qualified tips in a listed occupation; the overtime amount is only the premium part
  • The vehicle is new, assembled in the U.S., for personal use and secured by the loan
  • Married filing separately cannot claim tips, overtime or the senior deduction

Schedule AItemized Deductions

Included

  • Medical expenses above 7.5% of AGI
  • State and local income, real estate and personal property taxes with the $40,000 SALT limit and its reduction above $500,000
  • Mortgage interest from Form 1098 and cash and noncash gifts to charity (60% and 30% of AGI limits)

Not Included

  • The sales tax election, other taxes, investment interest (Form 4952), casualty losses, charity carryovers and other itemized deductions

Assumed

  • Mortgage debt is within the $750,000 acquisition-debt limit and points are on the 1098
  • Gifts go to public charities; Form 8283 for noncash gifts is not shown
  • The lab uses whichever is larger, itemized or standard (a taxpayer may elect otherwise)

Schedule BInterest and Ordinary Dividends

Included

  • Interest from 1099-INT boxes 1 and 3 and K-1s
  • Ordinary dividends from 1099-DIV and K-1s

Not Included

  • Part III foreign account questions (FBAR), the savings bond exclusion (Form 8815), nominee and accrued interest adjustments, and original issue discount

Schedule CProfit or Loss From Business

Included

  • One business per return: 1099-NEC income plus other income, expense totals, and the home office by the simplified method ($5 per square foot, up to 300)

Not Included

  • Cost of goods sold and inventory, depreciation and section 179, the regular home office method (Form 8829)
  • At-risk, hobby-loss and excess business loss limits

Assumed

  • Cash method of accounting
  • Meals are entered at the deductible 50%

Schedule DCapital Gains and Losses (with Form 8949)

Included

  • Short- and long-term sales from 1099-B, with Form 8949 boxes A, B, D and E and wash sale adjustments
  • Long-term gains from K-1s and capital gain distributions
  • The $3,000 capital loss limit ($1,500 married filing separately)

Not Included

  • Capital loss carryovers from earlier years (the carryover to next year is noted but not tracked)
  • Collectibles (28%) and unrecaptured section 1250 gain, Form 4797, installment sales and Form 1099-DA

Assumed

  • Each 1099-B slip is a summary of one category of sales

Schedule ESupplemental Income and Loss

Included

  • One residential rental property, with the Form 8582 limit applied to a loss
  • Partnership and S corporation K-1 income, passive and nonpassive

Not Included

  • Royalties, more than one property, vacation-home (personal use) rules and Part III estate and trust business income
  • At-risk and basis limits and section 179 from K-1s

Assumed

  • Rental depreciation is straight line over 27.5 years for a full year (building placed in service before 2025; the first-year mid-month convention is not applied)
  • The building cost entered excludes land

Schedule SESelf-Employment Tax

Included

  • Schedule C profit and K-1 box 14 code A, coordinated with W-2 Social Security wages for the $176,100 wage base

Not Included

  • Farm income, the optional methods, church employee income and Conservation Reserve payments

Assumed

  • One person on the return has self-employment income (the business owner)

Schedule 8812Credits for Qualifying Children and Other Dependents

Included

  • $2,200 per qualifying child, $500 per other dependent, the phase-out, and the refundable additional child tax credit (including Part II-B for three or more children)

Assumed

  • Children have SSNs and meet the age, relationship, residency and support tests
  • Credit Limit Worksheet A uses the Schedule 3 credits on lines 1–4

Form 8995Qualified Business Income Deduction — Simplified

Included

  • QBI from Schedule C (less the deductible part of SE tax) and from K-1s, the 20% component and the income limit

Not Included

  • REIT dividends and publicly traded partnership income, QBI loss carryforwards, aggregation and cooperative rules

Assumed

  • Rentals are not treated as a trade or business for QBI

Form 8995-AQualified Business Income Deduction

Included

  • Per-business W-2 wage and property (UBIA) limits, the phase-in range, and the specified service business phase-out

Not Included

  • REIT/PTP income, loss carryforwards, aggregation and patron reductions

Assumed

  • K-1 QBI, W-2 wages and UBIA are taken from box 20 code Z or box 17 code V as entered

Form 8863Education Credits

Included

  • American opportunity credit per student (up to $2,500, 40% refundable) and lifetime learning credit (20% of up to $10,000), with phase-outs

Not Included

  • The four-year limit, half-time enrolment and conviction tests (assumed met)

Assumed

  • Qualified expenses are 1098-T box 1 minus scholarships in box 5
  • Married filing separately is not eligible; someone claimed as a dependent gets no refundable part

Form 2441Child and Dependent Care Expenses

Included

  • The $3,000 / $6,000 expense limits, the earned income limit, the 35%–20% rate table and the tax limit

Not Included

  • Dependent care benefits (W-2 box 10), prior-year expenses and deemed income for a student or disabled spouse

Assumed

  • Qualifying persons are children under 13 who lived with the taxpayer more than half the year
  • Married filing separately is not eligible

Form 8880Credit for Qualified Retirement Savings Contributions

Included

  • IRA and W-2 box 12 elective deferrals, reduced by retirement distributions, up to $2,000 each, at 50%, 20% or 10%

Assumed

  • Distributions in the testing period are the 2025 1099-Rs only
  • The age, student and dependent tests come from the taxpayer settings

Form 8959Additional Medicare Tax

Included

  • Additional Medicare Tax on Medicare wages and self-employment income, and the withholding reconciliation

Not Included

  • RRTA compensation and unreported tips

Form 8960Net Investment Income Tax

Included

  • Interest, dividends, net capital gain and passive rental and K-1 income; nonpassive trade or business income is removed

Not Included

  • Investment expense deductions, state tax allocation, CFC/PFIC and disposition adjustments

Assumed

  • Modified AGI equals AGI

Form 6251Alternative Minimum Tax — Individuals

Included

  • Line 1a add-back of the senior deduction, the SALT or standard deduction add-back, incentive stock options, the exemption phase-out, the 26% / 28% rates and Part III capital gain rates

Not Included

  • Other adjustments and preferences (private activity bonds, depreciation, NOLs, passive differences) and the AMT credit carryforward (Form 8801)

Assumed

  • The AMT foreign tax credit equals the regular foreign tax credit

Form 1116Foreign Tax Credit (passive category, simplified)

Included

  • Passive category foreign tax from 1099-DIV and 1099-INT, and the $300 / $600 election to skip Form 1116 when it applies

Not Included

  • Qualified dividend and capital gain rate adjustments, carryovers and carrybacks, other categories and the high-tax kickout

Assumed

  • Deductions are apportioned by the ratio of foreign to total gross income
  • Unused foreign tax carries over but is not tracked

Form 8582Passive Activity Loss Limitations

Included

  • The $25,000 special allowance for rental real estate with active participation, reduced by 50% of MAGI over $100,000, and passive income offsetting the loss

Not Included

  • Limits on passive K-1 losses (they are not limited in this lab), prior-year unallowed losses and real estate professional status

Assumed

  • Married filing separately gets no special allowance
  • MAGI is simplified to AGI before the rental loss

SS WorksheetSocial Security Benefits Worksheet

Included

  • The standard Social Security Benefits Worksheet (lines 1–18)

Not Included

  • The lump-sum election and railroad retirement benefits

Assumed

  • Married filing separately is treated as living with the spouse (base amount $0)

EIC WorksheetEarned Income Credit Worksheet

Included

  • The EIC Table method (middle of each $50 row) on earned income and AGI, with the investment income limit of $11,950

Not Included

  • The separated-spouse rule for married filing separately, disallowance periods and the combat pay election

Assumed

  • Qualifying children are under 19, or under 24 and full-time students, and lived with the taxpayer more than half the year
  • Valid SSNs and U.S. residency

QD & CG WorksheetQualified Dividends and Capital Gain Tax Worksheet

Included

  • The 0%, 15% and 20% rates on qualified dividends and net capital gain, using the Tax Table for amounts under $100,000

Not Included

  • The Schedule D Tax Worksheet for 28% and unrecaptured section 1250 gain, and the Form 4952 election

This is an educational training tool. It is not tax advice and does not prepare or file real returns.

US Tax Training · Corporate Tax

Form 1120 Lab

  • Calendar-year 2025, domestic C corporation, separate federal return. State returns are not included.
  • Rules follow the 2025 forms and the 2025 tax law changes (100% bonus depreciation, section 174A, the EBITDA-based 163(j) limit and the $2.5 million section 179 limit).
  • All companies, people and amounts are fictional; the lab does not prepare or file real returns.

Form 1120U.S. Corporation Income Tax Return

Included

  • Pages 1 and 6 of the 2025 Form 1120 for a calendar-year domestic C corporation filing a separate (non-consolidated) return
  • The 21% flat rate, payments, the estimated tax penalty and the refund or amount owed

Not Included

  • Consolidated returns (Form 851), personal holding company tax, life and insurance companies, the section 1062 farmland installment election and Form 1125-E detail
  • Accumulated earnings tax and state returns

Assumed

  • Accrual method, December 31 year end, U.S. trade or business only
  • Federal income tax recorded in the books is the book provision, not the tax on the return

Schedule CDividends, Inclusions and Special Deductions

Included

  • 50%, 65% and 100% dividends-received deductions, the section 245A deduction, Subpart F, GILTI, the section 78 gross-up and the section 250 deduction

Not Included

  • Debt-financed stock (line 3), public utility preferred stock, IC-DISC, FSC and hybrid dividends

Assumed

  • Holding periods are met (46 days, or 1 year for section 245A)

DRD LimitDividends-Received Deduction Limit Worksheet

Included

  • The section 246(b) taxable income limit (65% first, then 50%), with line 28 reduced by the 100% deductions on Schedule C lines 10–12, and the NOL exception

Assumed

  • No capital loss carryback or section 1059 adjustment

Schedule JTax Computation and Payment

Included

  • Regular tax, CAMT, the foreign tax credit and the general business credit, estimated payments and extension deposits

Not Included

  • BEAT amounts, personal holding company tax, recapture taxes, deferred tax items and refundable credits

Schedule KOther Information · selected questions

Included

  • A few questions that the numbers answer: accounting method, tax-exempt interest, NOL carryover, the $250,000 test, BEAT, Form 8990 and CAMT

Not Included

  • The other ownership and reporting questions on pages 4–5

Schedule LBalance Sheet per Books · end of year (column d)

Included

  • Year-end book balances (column d), with retained earnings from Schedule M-2

Not Included

  • The beginning-of-year columns (a) and (b)

Assumed

  • Cash is the balancing figure in the case records

Schedule M-1Reconciliation of Income (Loss) per Books With Income per Return

Included

  • Book-tax differences: tax expense, capital losses, inclusions, depreciation, contributions, meals and entertainment, fines, life insurance, foreign taxes, research costs, interest and tax-exempt interest

Assumed

  • Used when total assets are under $10 million

Schedule M-3Net Income (Loss) Reconciliation for Corporations With Total Assets of $10 Million or More · key lines

Included

  • Part I line 11 and the Part II and Part III lines that carry differences in these cases, split into temporary (b) and permanent (c) columns
  • Line 30 ties column (a) to book income and column (d) to Form 1120, line 28

Not Included

  • Parts I lines 1–10 and 12 (consolidation items) and lines with no differences, which are combined on Part II, line 28

Assumed

  • Required instead of Schedule M-1 when total assets are $10 million or more

Schedule M-2Analysis of Unappropriated Retained Earnings per Books

Included

  • Retained earnings roll-forward with book income and cash dividends

Not Included

  • Stock and property distributions and appropriated retained earnings

Form 1125-ACost of Goods Sold

Included

  • All eight lines

Assumed

  • Section 263A costs are given; the simplified production method is assumed

Form 4562Depreciation and Amortization

Included

  • Section 179 (2025 limits), bonus depreciation at 100% or 40%, half-year MACRS for 5-, 7- and 15-year property and mid-month for 39-year buildings, and prior-year MACRS from the asset schedule

Not Included

  • The mid-quarter convention, listed property, amortization (Part VI) and ADS

Assumed

  • Bonus applies to new 5-, 7- and 15-year property unless the election out is ticked; buildings get no bonus

Form 4797Sales of Business Property

Included

  • Section 1231 netting, the five-year lookback, section 1245 recapture, the corporate section 291 recapture on buildings and short-term business property

Not Included

  • Casualties (Form 4684), installment sales (Form 6252), like-kind exchanges (Form 8824) and Part IV

Assumed

  • MACRS buildings use straight-line, so only section 291 applies to them

Schedule DCapital Gains and Losses (Form 1120)

Included

  • Short- and long-term sales from Form 8949, section 1231 gain from Form 4797 and the five-year capital loss carryover

Not Included

  • Capital gain distributions, installment and like-kind gains, and the three-year carryback

Assumed

  • All carryover years are within five years

Form 8949Sales and Other Dispositions of Capital Assets · gain or loss per sale

Included

  • One gain or loss per sale (column h), basis reported to the IRS (box A or D)

Not Included

  • Adjustment codes and wash sales

Charitable LimitCharitable Contributions Limit Worksheet

Included

  • The 10% limit, current gifts before carryovers, and the five-year carryover

Not Included

  • Inventory and property contributions, and the 2026 rules

Assumed

  • Taxable income for the limit includes the NOL carryforward deduction but not special deductions

NOLNet Operating Loss Deduction Worksheet

Included

  • Post-2017 NOLs and the 80% limit

Not Included

  • Pre-2018 NOLs, carrybacks (farm and insurance only) and section 382 limits

Form 1118Foreign Tax Credit—Corporations · key lines

Included

  • The general category (direct taxes on foreign royalties and Subpart F taxes deemed paid) and the section 951A category, with the limitation fraction and Schedule B, Part III

Not Included

  • Schedules C to H in full, the passive and foreign branch categories, carryover schedules and boycott reductions

Assumed

  • Deductions are apportioned by the gross income method (a simplification of Schedule H); none are apportioned to GILTI beyond the section 250 deduction

Form 4626Alternative Minimum Tax—Corporations (CAMT)

Included

  • Part I: the $1 billion three-year average test
  • Part II for an applicable corporation: book income, the tax expense and depreciation adjustments, CFC income, 15% tentative minimum tax and the CAMT

Not Included

  • The foreign-parented group test, the $100 million test, financial statement NOLs, partnership and other adjustments, and the minimum tax credit

Assumed

  • Average AFSI for 2022–2024 is given in the case records

Form 8990Limitation on Business Interest Expense Under Section 163(j)

Included

  • The 30% of ATI limit with the restored depreciation add-back, business interest income and carryforwards

Not Included

  • Floor plan interest, pass-through items, the real property and farming elections

Assumed

  • All interest is business interest; the small business exemption uses the average gross receipts given ($31 million for 2025)

Form 2220Underpayment of Estimated Tax by Corporations

Included

  • The regular installment method, the prior-year safe harbor, the large-corporation rule (first installment only on last year's tax, catch-up in the second), payments applied to the earliest underpayment, and the 7% and 6% rates through April 15, 2026

Not Included

  • The annualized and adjusted seasonal installment methods

Assumed

  • Estimated payments are made on the due dates; the penalty runs to April 15, 2026

Form 6765Credit for Increasing Research Activities · Section B (ASC)

Included

  • The alternative simplified credit and the section 280C reduced-credit election

Not Included

  • The regular credit (Section A), basic research payments, the payroll tax election and Section G detail

Assumed

  • QREs are a subset of the domestic research costs

Section 174AResearch and Experimental Expenditures Worksheet

Included

  • Section 174A expensing of domestic research, 15-year amortization of foreign research and the deduction of unamortized 2022–2024 domestic research in 2025

Not Included

  • The two-year spread option and amended returns for small businesses

Assumed

  • The research deduction is reported on Form 1120, line 26

Form 3800General Business Credit · key lines

Included

  • The general business credit limit with the 25% rule

Not Included

  • Specified credits, carryback and carryforward detail

Assumed

  • The tentative minimum tax is treated as zero for a corporation

Form 8992U.S. Shareholder Calculation of GILTI

Included

  • Net CFC tested income, the 10% QBAI return less interest, GILTI, the inclusion percentage, the section 78 gross-up and the 80% deemed-paid taxes

Not Included

  • Schedule A detail, tested income and loss of each CFC on its own row, the high-tax exclusion and PTEP

Assumed

  • The corporation owns 100% of each CFC for the whole year

Form 8993Section 250 Deduction for FDII and GILTI

Included

  • DEI, the 10% QBAI return, FDDEI, the foreign-derived ratio, FDII, GILTI and the taxable income limit, with the 2025 rates

Not Included

  • Detailed allocation of deductions to DEI and FDDEI

Assumed

  • DEI is line 28 less all dividends, inclusions and gross-ups; foreign-derived sales and their costs are given

Form 8991Base Erosion Minimum Tax · Part I applicable taxpayer test

Included

  • The $500 million gross receipts test and the 3% base erosion percentage test

Not Included

  • Parts II–V: modified taxable income and the BEAT itself

Assumed

  • The cases are not applicable taxpayers

DPAD (History)Domestic Production Activities Deduction · history note

Included

  • A history note on the repealed domestic production activities deduction

Not Included

  • Any 2025 calculation: the deduction does not apply after 2017