US Tax Tools

Tax Insights & Guides

Clear, practical explanations of federal tax topics — from brackets and deductions to retirement accounts and self-employment tax.

Income Tax

FEIE vs Foreign Tax Credit: Which to Use (and When You Need Both)

Decision framework for US expats: when the Foreign Earned Income Exclusion saves more, when the Foreign Tax Credit wins, and how to combine them with the housing exclusion.

FEIE foreign-tax-credit expat-taxes
Income Tax

FBAR vs FATCA: Why You Probably Need to File Both

FBAR (FinCEN 114) and FATCA (Form 8938) are separate reports with different thresholds, penalties, and forms. A side-by-side breakdown of who files what, when, and why filing only one isn't enough.

FBAR FATCA FinCEN-114
Income Tax

Streamlined Procedure: IRS Catch-Up Filing for US Expats

If you're a US citizen or green card holder living abroad and missed filing — the Streamlined Filing Compliance Procedures let you catch up without penalties. 3 years of returns, 6 years of FBAR, non-willful certification.

streamlined-procedure expat-taxes FBAR
Investment

83(b) Election Deadline and How to File: 30 Days From Grant

The Section 83(b) election has a hard 30-day filing window from the grant or early-exercise date. Late filings are rejected without exception. Step-by-step on what goes in the statement, how to mail it, and what records to keep.

83b stock-options equity
Investment

Double-Trigger RSUs Explained: Pre-IPO Tax, IPO Day, and the 22% Trap

Most private tech companies grant double-trigger RSUs that defer income recognition until both time vest AND a liquidity event. The structure protects employees from owing tax on illiquid stock — but creates a multi-million-dollar single-day income event at IPO with a punishing supplemental-withholding gap.

rsu pre-ipo double-trigger
Investment

ESPP Qualifying vs Disqualifying Disposition: Lesser-of Rule, FICA Exemption, and the Lookback

§423 Employee Stock Purchase Plans use a 'lesser-of' rule on qualifying dispositions that trips up most tax software defaults. Plus the FICA exemption that survives both qualifying AND disqualifying treatment, and how the 15% lookback discount produces ordinary-income recognition that exceeds the actual gain.

espp stock-compensation equity
Investment

The $100,000 ISO Limit Explained: When ISOs Auto-Convert to NSOs

IRC §422(d) caps the aggregate fair market value of stock that can become first-exercisable in any one calendar year as ISO at $100,000 per employee. Anything above is automatically reclassified as NSO regardless of grant agreement. How to detect when you trip the cap and what changes when you do.

iso nso stock-options
Investment

QSBS Exemption Guide: How Section 1202 Excludes Up to 100% of Founder Gain

Qualified Small Business Stock under IRC §1202 lets eligible founders and early employees exclude federal capital gains tax — up to the greater of $10 million or 10× basis per issuer — when selling C-corp stock held five years. The qualification tests, the 5-year hold, the $50M aggregate-asset cap, and which states refuse to conform.

qsbs section-1202 founder-tax
Investment

RSU Sell-to-Cover Explained: How Many Shares Disappear at Vest

Sell-to-cover withholds shares at vest to pay federal tax (typically 22% supplemental), Social Security, Medicare, and state. Why your net-share count is always less than you expected, the supplemental withholding gap, and when same-day-sale or cash withholding is the better choice.

rsu stock-compensation equity
Investment

RSU 1099-B Cost Basis Correction: Form 8949 Code B Walkthrough

Brokerages routinely report $0 cost basis on Form 1099-B for RSU and ESPP sales — even though you already paid ordinary income tax on the vest-day FMV. Without a basis correction on Form 8949, you pay tax twice on the same dollars. Step-by-step on the code B adjustment.

rsu espp stock-compensation
Planning

Estate Tax 2026: OBBBA's $15M Permanent Exemption Replaces the TCJA Sunset

OBBBA (signed July 2025) made a $15 million per-person estate and gift tax exemption permanent starting 2026, replacing the scheduled TCJA sunset to ~$7M. What this means for estate planning, the end of 'use it or lose it' urgency, and which strategies still matter.

estate-tax gift-tax OBBBA
Retirement

401(k) Catch-Up Age 60-63 Enhanced Contribution 2026 — SECURE 2.0 $11,250 Boost (IRS)

The SECURE 2.0 §109 super catch-up for ages 60-63: $11,250 instead of $7,500 in 2026, the 150% formula, Roth-mandate for high earners from 2026, IRS §415 total cap, and a worked example for a 62-year-old earning $200,000.

401k retirement catch-up
Income Tax

IRS Amended Return 1040-X Refund Timing 2026 — Where's My Refund & 16 Weeks (IRS)

How long a Form 1040-X amended return takes in 2026: 16-20 week normal processing, the separate Where's My Amended Return tracker, delay causes, statutory interest paid after 45 days, and a $2,500 refund worked example.

amended-return 1040-x refund
Self-Employment

Q2 Estimated Tax Due June 15 2026 — Safe Harbor, Form 1040-ES, and Penalties (IRS)

Complete guide to the Q2 2026 estimated tax payment due June 15: safe harbor rules (100%/110%/90%), Form 1040-ES vouchers vs EFTPS vs IRS Direct Pay, underpayment penalty math, and a worked freelancer example.

quarterly-tax estimated-payments self-employment
Self-Employment

Estimated Tax Underpayment Penalty: How It's Calculated and How to Avoid It

The IRS charges an underpayment penalty when you don't pay enough tax throughout the year. Learn exactly how the safe harbor rules work, 2025 quarterly due dates, and the annualized income method for uneven earners.

underpayment-penalty estimated-tax safe-harbor
Investment

RSU Tax Guide: How Restricted Stock Units Are Taxed at Vesting and Sale

Restricted stock units are taxed twice — once as ordinary income at vest, again as capital gains at sale. A complete guide to withholding, double-taxation traps, and the tax-smart way to manage your RSU grant.

rsu stock-compensation equity
Income Tax

How to File an Amended Tax Return (Form 1040-X) After April 15

Missed a deduction, forgot a 1099, or filed with the wrong filing status? A clear walkthrough of when and how to file Form 1040-X, the three-year deadline, and what to expect for refunds or additional tax owed.

amended-return 1040-x irs
Investment

1031 Exchange Explained: Defer Capital Gains Tax on Real Estate

Learn how a 1031 like-kind exchange lets real estate investors defer capital gains tax indefinitely, including timelines, boot rules, depreciation recapture, and a worked example showing the math.

1031-exchange real-estate capital-gains
Planning

Dependent Care Benefits: FSA, Tax Credit, and Which Saves More

Compare the Dependent Care FSA and the Child and Dependent Care Tax Credit side by side. See which saves more at your income level, whether you can use both, and how to maximize your childcare tax breaks in 2026.

dependent-care fsa childcare
Investment

Wash Sale Rule: What Investors Need to Know Before Tax-Loss Harvesting

The wash sale rule can turn a smart tax-loss harvesting move into a costly mistake. Learn the 61-day window, how disallowed losses work, the IRA trap, and strategies to harvest losses legally.

wash-sale tax-loss-harvesting investing
Planning

ACA Premium Tax Credit: Income Limits, Subsidy Amounts, and How to Estimate Your Savings

How the ACA premium tax credit works, who qualifies, how subsidies are calculated, and how to avoid overpayment surprises at tax time.

ACA premium tax credit health insurance
Income Tax

FEIE 2026 & 2025: $132,900 / $130k Foreign Earned Income Exclusion for Expats

FEIE 2026 = $132,900 ($130k 2025) — exclude foreign earned income for US expats. Bona Fide Residence / Physical Presence test, Form 2555 + housing exclusion.

FEIE foreign income expat taxes
State Tax

Sales Tax by State: Combined Rates, Exemptions, and How to Calculate What You Owe

State and local sales tax rates across the US, which states have no sales tax, common exemptions, and how combined rates affect what you pay.

sales tax state tax exemptions
Self-Employment

1099 Filing Deadlines and Penalties 2026

1099-NEC is due January 31, 2026. Learn all 1099 filing deadlines, late filing penalties ($60–$310 per form), intentional disregard penalties, and how to avoid IRS enforcement.

1099 self-employment deadlines
Deductions

2026 EITC Amounts and Income Limits

2026 Earned Income Tax Credit maximum amounts by number of children, income phase-out ranges, and the investment income limit. See if you qualify and how much you can claim.

eitc credits
Retirement

2026 Retirement Contribution Limits

2026 projected contribution limits for 401(k), IRA, Roth IRA, HSA, and catch-up contributions compared to 2025. Maximize your tax-advantaged retirement savings with the updated numbers.

retirement 401k ira
Income Tax

2026 Federal Tax Bracket Changes

Inflation-adjusted 2026 federal tax brackets compared side-by-side with 2025. See exactly how the ~2.8% adjustment affects each rate threshold and what it means for your tax bill.

income-tax tax-brackets federal-tax
Investment

2026 Capital Gains Tax Rates — 0% / 15% / 20% Income Thresholds (& NIIT)

2026 IRS capital gains tax thresholds: 0% rate up to $48,350 single / $96,700 MFJ, 15% to $533,400 / $600,050, then 20% — plus 3.8% NIIT, collectibles 28%, and depreciation recapture 25%.

capital-gains investment tax-rates
Retirement

2026 Social Security COLA and Tax Changes

Projected 2026 Social Security COLA of ~2.5%, the new taxable wage base cap, and how benefit taxation thresholds affect retirees. What every Social Security recipient needs to know.

social-security retirement
Deductions

2026 Standard Deduction Amounts

The IRS has increased the 2026 standard deduction to $16,100 for single filers and $32,200 for married filing jointly (per Rev. Proc. 2025-32). See full amounts by filing status and how they compare to OBBBA-adjusted 2025 numbers.

deductions standard-deduction
Retirement

401(k) Contribution Limits for 2026

The 2026 401(k) contribution limits, including employee deferrals, catch-up contributions, employer match rules, and how Roth 401(k) fits in.

401k retirement contribution-limits
State Tax

2026 State Tax Ranking: Biggest Movers

Which states improved the most in tax competitiveness for 2026? Rate cuts, new flat taxes, and expanding no-income-tax states are reshaping the state tax landscape.

state-tax no-income-tax state-comparison
Retirement

Backdoor Roth IRA: How High Earners Can Still Fund a Roth

If you earn too much to contribute directly to a Roth IRA, the backdoor Roth strategy lets you get money in anyway. Here's how it works, the tax implications, and the pro-rata rule you need to watch for.

roth-ira backdoor-roth retirement
Deductions

Child Tax Credit 2025 & 2026: Eligibility, Amounts & Phase-Outs

How the Child Tax Credit works in 2025 and 2026 — the $2,200 per child amount after OBBBA, income phase-out thresholds, the refundable Additional Child Tax Credit, and who qualifies.

child-tax-credit credits dependents
Investment

Crypto Tax Basics: What Triggers a Taxable Event

Understand which crypto transactions are taxable — selling, trading, and earning — and which are not. How cost basis methods work, and how to report on Form 8949.

crypto capital-gains investment
Income Tax

How Federal Tax Brackets Work

Learn the difference between marginal and effective tax rates, see the 2025 federal tax bracket tables, and follow a step-by-step worked example at an $85,000 salary.

income-tax tax-brackets federal-tax
Investment

How Capital Gains Tax Is Calculated

Understand short-term vs long-term capital gains rates, how cost basis works, and the wash sale rule — with clear examples for investors.

capital-gains investment tax-rates
State Tax

How State Income Tax Works

Progressive vs flat vs no state income tax — how state tax systems differ, how state tax interacts with federal, and the impact of the SALT deduction cap.

state-tax state-comparison
Deductions

HSA vs. FSA: Which Health Account Is Better?

Compare Health Savings Accounts and Flexible Spending Accounts on tax advantages, contribution limits, eligible expenses, and long-term saving potential to find the right fit for your situation.

deductions credits
Deductions

Is It Worth Itemizing Deductions Anymore? 2025 & 2026 OBBBA SALT Cap Update

OBBBA (signed July 2025) raised the SALT cap to $40,000 ($40,400 in 2026) and made the higher standard deduction permanent. Understand when itemizing still wins for homeowners, donors, and high-medical-expense filers.

deductions itemized standard-deduction
Self-Employment

LLC vs. S-Corp: Which Business Structure Saves More in Taxes?

Compare the tax implications of an LLC versus an S-Corp for self-employed individuals, including SE tax savings, reasonable salary requirements, and compliance costs.

self-employment 1099 business-structure
Planning

IRS Tax Deadlines 2026: Complete Calendar

Every important IRS tax deadline for 2026 in one place — from January estimated tax payments through the October extension deadline, with penalties for missing each date.

tax-planning deadlines
State Tax

Moving to a No-Income-Tax State: Is It Actually Worth It?

Explore whether relocating to one of the 9 states with no income tax truly saves money — considering property taxes, sales taxes, cost of living, and remote work tax complications.

state-tax no-income-tax moving
Self-Employment

Quarterly Estimated Tax Payments Explained

Who must pay estimated taxes, how the safe harbor rules work, how to avoid underpayment penalties, and the 2026 due dates for quarterly payments.

quarterly-tax estimated-tax self-employment
Retirement

Roth Conversion: When Does It Make Sense?

Learn when converting a Traditional IRA or 401(k) to a Roth makes financial sense — covering low-income years, early retirement gap years, and tax bracket management.

roth ira retirement
Self-Employment

Self-Employment Tax: How It Works

Understand the 15.3% self-employment tax, how to deduct half of it, what Schedule SE requires, and how it differs from W-2 FICA withholding.

self-employment fica schedule-c
Planning

Should You Pay Off Your Mortgage or Invest the Money?

Analyze whether paying off your mortgage early or investing extra cash produces better after-tax returns — accounting for mortgage interest deductions, expected investment returns, and risk tolerance.

deductions investment mortgage
Retirement

Should You Max Out Your 401(k) or Invest in a Brokerage Account?

Compare tax-deferred 401(k) contributions against taxable brokerage investing to find the right balance for your retirement and financial goals.

401k retirement investment
Deductions

Standard vs. Itemized Deductions: Which Should You Choose?

Compare the 2025 standard deduction amounts with common itemized deductions, and use a breakeven analysis to determine which method lowers your tax bill.

deductions standard-deduction itemized
State Tax

States That Changed Tax Rates in 2026

Which states cut or restructured income tax rates effective 2026? Iowa, Georgia, Mississippi, and others continue phased reforms. See the impact on take-home pay by state.

state-tax state-comparison
Retirement

Traditional vs. Roth 401(k): Which Should You Pick?

Compare Traditional and Roth 401(k) contributions to determine which option saves you more tax based on your current income, expected future tax rate, and retirement timeline.

401k roth retirement
Income Tax

Understanding FICA: Social Security and Medicare Taxes

A complete guide to FICA payroll taxes — the 6.2% Social Security tax, 1.45% Medicare tax, wage base cap, and the Additional Medicare Tax at $200,000.

fica social-security medicare
Retirement

When to Take Social Security: The Tax Impact of Age 62 vs. 67 vs. 70

Understand how the age you claim Social Security affects your benefit amount, federal tax exposure, and breakeven timeline — and how to minimize the tax hit on your benefits.

social-security retirement tax-planning
Self-Employment

W-2 vs. 1099: Tax Differences Explained

Understand the key tax differences between W-2 employee income and 1099 independent contractor income — including self-employment tax, withholding, deductions, and benefits.

1099 self-employment freelance
Planning

Alternative Minimum Tax (AMT) Explained: Who Pays It in 2025

Understand how the Alternative Minimum Tax works, the 2025 AMT exemption amounts, income triggers, and strategies to avoid or minimize AMT liability.

amt alternative-minimum-tax tax-planning
Income Tax

Child Tax Credit 2025 & 2026: $2,200 Per Child After OBBBA

Understand the 2025 and 2026 Child Tax Credit — $2,200 per child after the One, Big, Beautiful Bill Act, income phase-out thresholds, refundability rules, and the Additional Child Tax Credit for lower-income families.

child-tax-credit tax-credits family
Planning

Education Tax Credits Explained: AOTC vs. Lifetime Learning Credit

Compare the American Opportunity Tax Credit and Lifetime Learning Credit — eligibility rules, dollar amounts, income limits, and which credit gives you the bigger tax break in 2025.

education tax-credits american-opportunity-credit
Income Tax

Earned Income Tax Credit (EITC): Who Qualifies and How Much You Can Get

Learn who qualifies for the Earned Income Tax Credit in 2025, the income limits, credit amounts by number of children, and common mistakes that cost filers this valuable refundable credit.

eitc earned-income-credit tax-credits
Planning

Gift Tax 2025 & 2026 — $19,000 Annual Exclusion & $15M Lifetime (OBBBA)

2025 and 2026 gift tax rules: $19,000 annual exclusion per recipient, lifetime exemption now $15M per person in 2026 (OBBBA permanent), when you must file Form 709, and smart gifting strategies.

gift-tax estate-planning annual-exclusion
Deductions

Home Office Deduction Guide: Who Qualifies and How to Calculate It

Learn who can claim the home office deduction, the difference between the simplified and regular methods, and what expenses qualify — including key rules for remote employees.

home-office deductions self-employment
Investment

Qualified vs. Ordinary Dividends: How Each Is Taxed

Learn the difference between qualified and ordinary dividends, the holding period requirement, and how each type affects your federal tax bill in 2025.

dividends investment qualified-dividends
Investment

Tax-Loss Harvesting: Turn Investment Losses Into Tax Savings

A complete guide to tax-loss harvesting — how to offset capital gains with losses, avoid the wash-sale rule, and reduce your tax bill without changing your investment strategy.

tax-loss-harvesting capital-gains investment
Investment

Crypto Tax Guide 2025: How Bitcoin, Staking, and DeFi Are Taxed

Complete guide to cryptocurrency taxation in 2025 covering trading, mining, staking, airdrops, DeFi, NFTs, and capital loss harvesting strategies.

crypto bitcoin capital-gains
Planning

Marriage Tax Penalty vs. Bonus: How Marriage Affects Your Taxes

Learn when marriage creates a tax penalty or bonus, how filing jointly vs. separately compares, and the impact on credits, deductions, and tax brackets.

marriage filing-status tax-planning
State Tax

Moving to a New State? Here Is How It Affects Your Taxes

Understand the tax implications of moving between states, including partial-year residency rules, remote work taxation, and no-income-tax state strategies.

state-tax moving remote-work
Self-Employment

Side Hustle Tax Guide: How Gig Income Is Taxed in 2025

Learn how side income and gig work is taxed, including 1099-K reporting, estimated taxes, common deductions, and the hobby vs. business distinction.

side-hustle gig-economy self-employment
Retirement

When Are Social Security Benefits Taxed? A Complete Guide

Understand when and how Social Security benefits are taxed, including the provisional income formula, 50% and 85% thresholds, and strategies to reduce taxation.

social-security retirement taxation
Deductions

Student Loan Tax Deductions and Forgiveness: What You Need to Know

Guide to the student loan interest deduction, income phase-outs, IDR plan tax implications, loan forgiveness taxation, and employer assistance programs.

student-loans deductions education
Planning

10 Common Tax Filing Mistakes to Avoid in 2025

Avoid costly tax filing errors with this guide to the most common mistakes taxpayers make, from wrong filing status to missed deductions and deadlines.

tax-filing mistakes tips
Planning

Year-End Tax Planning Strategies to Lower Your 2025 Tax Bill

Smart December tax moves including tax-loss harvesting, charitable donation bunching, Roth conversions, 401(k) maxing, HSA contributions, and income timing.

tax-planning year-end strategies
Self-Employment

1099 Freelancer Tax Guide: Everything You Need to Know for 2025

A complete guide to 1099 freelancer taxes in 2025: self-employment tax, quarterly payments, top deductions, and exactly how much to set aside so you never get blindsided at tax time.

1099 freelance self-employment
Deductions

Depreciation, Section 179, and Bonus Depreciation: A Business Owner's Guide for 2025

How MACRS depreciation works, when to use Section 179 expensing, and what business owners need to know about bonus depreciation in 2025 — with practical examples and vehicle rules.

depreciation section-179 bonus-depreciation
Planning

Estate Planning Tax Basics 2025 & 2026 — $15M OBBBA Exemption & Strategies

2025 and 2026 federal estate tax exemption (OBBBA made $15M per-person permanent starting 2026), annual gift tax exclusion, marital deduction, portability, and key planning strategies to minimize estate taxes and preserve wealth for your heirs.

estate-tax gift-tax estate-planning
Income Tax

Lottery and Gambling Tax Guide: How Winnings Are Taxed in 2025

How lottery winnings and gambling income are taxed at the federal and state level in 2025, including lump sum vs. annuity decisions, withholding rules, and how to deduct gambling losses.

gambling-tax lottery-tax winnings
State Tax

Property Tax by State: How It Works, Rates, and Exemptions (2025)

A complete guide to property taxes in the US: how assessed value and mill rates work, which states have the highest and lowest property taxes, and the exemptions that can reduce your bill.

property-tax real-estate state-tax
Investment

Rental Property Tax Guide: Depreciation, Deductions, and Passive Loss Rules (2025)

How rental income is taxed in 2025: what you can deduct, how depreciation works, the passive activity loss rules, and how to calculate your real after-tax cash flow.

rental-income real-estate depreciation
Income Tax

2025 Federal Tax Brackets Explained

Understand how the 7 federal income tax brackets work in 2025, including rates for single and married filing jointly, and how progressive taxation really applies to your income.

tax-brackets 2025 federal-tax
Deductions

Standard vs. Itemized Deduction in 2025: Which Should You Choose?

Compare the 2025 standard deduction amounts with itemized deductions to determine which option saves you more on your federal tax return.

deductions standard-deduction itemized
Income Tax

How FICA Tax Works: Social Security and Medicare Explained

Learn how FICA taxes are calculated, including Social Security and Medicare rates, wage base limits, and the additional Medicare tax for high earners.

fica social-security medicare
Retirement

Roth vs. Traditional IRA: Which Is Better for You?

Compare Roth and Traditional IRAs to determine which retirement account type best fits your tax situation, income level, and long-term financial goals.

roth-ira traditional-ira retirement
Self-Employment

Self-Employment Tax Guide: What Freelancers and 1099 Workers Need to Know

A complete guide to self-employment tax for freelancers and independent contractors, including the 15.3% SE tax rate, deductions, and quarterly estimated payment due dates.

self-employment 1099 freelance
Investment

Capital Gains Tax Rates in 2025: What Investors Need to Know

Understand 2025 capital gains tax rates for short-term and long-term investments, including the 0%, 15%, and 20% brackets, NIIT, and tax-loss harvesting strategies.

capital-gains investment long-term
Retirement

Maximize Your 401(k) in 2025: Contribution Limits and Strategies

Learn the 2025 401(k) contribution limits, catch-up contributions, employer match strategies, and how to calculate the true cost of your retirement savings.

401k employer-match retirement
State Tax

States With No Income Tax: The Complete Guide

Explore all 9 U.S. states with no income tax, learn what they tax instead, and understand the hidden costs and trade-offs of living in a no-income-tax state.

state-tax no-income-tax state-comparison
Self-Employment

Quarterly Estimated Tax Payments: Who Needs to Pay and How to Calculate

Learn who must make quarterly estimated tax payments, the 2026 due dates, how to calculate your payments, the safe harbor rule, and how to avoid underpayment penalties.

quarterly-tax estimated-payments self-employment
Planning

The HSA Triple Tax Advantage: The Most Powerful Tax-Sheltered Account

Discover the triple tax advantage of Health Savings Accounts, including 2025 contribution limits, investment strategies, and how to use your HSA as a retirement tool.

hsa health-savings tax-advantage

Last updated May 1, 2026 Tax year 2025-26

Data sources: IRS (irs.gov), Social Security Administration

This tool is general information only, not financial advice.

Reviewed by USTax Tools Editorial Desk

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