What Are the Sources of Income? Types, Taxes, and Exclusions

Federal tax law starts from a simple premise: nearly every dollar you receive is taxable unless a specific rule says otherwise. That default shapes how the sources of income are taxed, because each category (wages, business profits, investment returns, rents, retirement distributions, government payments, and the occasional windfall) carries its own rate, its own reporting form, and its own set of exclusions. The Internal Revenue Code defines gross income as income from whatever source derived, which is why the burden usually falls on you to find the exclusion rather than on the IRS to prove the inclusion.1Office of the Law Revision Counsel. 26 USC 61 – Gross Income Defined

Wages, Salaries, and Self-Employment Earnings

Compensation for personal services is the largest income category for most people and the one the IRS watches most closely, because employers report every paycheck. The tax code calls this earned income and includes wages, salaries, tips, commissions, bonuses, and net self-employment earnings.2Office of the Law Revision Counsel. 26 USC 32 – Earned Income

If you work for an employer, FICA taxes come out of your check before you see it: 6.2% for Social Security and 1.45% for Medicare.3Internal Revenue Service. Topic No. 751, Social Security and Medicare Withholding Rates The Social Security portion applies only to the first $184,500 of earnings in 2026.4Social Security Administration. Contribution and Benefit Base Medicare has no cap. If your earnings exceed $200,000 (or $250,000 for married couples filing jointly), an additional 0.9% Medicare surtax applies to everything above that threshold.5Internal Revenue Service. Topic No. 560, Additional Medicare Tax

Self-employed workers pay both halves of FICA, a combined 15.3% on the first $184,500 of net earnings (12.4% Social Security plus 2.9% Medicare).6Internal Revenue Service. Self-Employment Tax (Social Security and Medicare Taxes) You can deduct the employer-equivalent half when calculating your adjusted gross income. Clients who pay you $2,000 or more during 2026 must send a Form 1099-NEC.7Internal Revenue Service. Form 1099-NEC and Independent Contractors Every dollar of self-employment income is taxable whether you receive a 1099 or not.

Fringe Benefits That Escape the W-2

Not everything your employer gives you counts as taxable wages. Employer-paid health insurance premiums, up to $50,000 of group life insurance coverage, retirement plan contributions, up to $5,250 in annual educational assistance, commuter benefits, HSA contributions within the annual limits, and small perks the IRS considers too minor to track are all excluded from your taxable income.8Internal Revenue Service. Publication 15-B, Employer’s Tax Guide to Fringe Benefits Because these dollars never become income, they are worth more than a raise of the same face value.

Interest, Dividends, and Capital Gains

Investment income falls into three main categories, and all three sit inside gross income under federal law.1Office of the Law Revision Counsel. 26 USC 61 – Gross Income Defined

Interest from savings accounts, CDs, and bonds is taxed as ordinary income at your regular rate. Dividends split in two. Qualified dividends, which come from most domestic stocks held for a required minimum period, are taxed at the preferential long-term capital gains rates of 0%, 15%, or 20% depending on your taxable income. Nonqualified dividends are taxed at ordinary rates, which can reach 37%.

Capital gains arise when you sell an asset for more than you paid for it. The tax rate depends on how long you held it. Assets owned for more than one year qualify for long-term rates (0%, 15%, or 20%), while assets held for a year or less are taxed as ordinary income.9Office of the Law Revision Counsel. 26 USC 1223 – Holding Period of Property That one-year mark is a meaningful line for anyone thinking about selling. Keeping records of your cost basis (what you originally paid) is essential, because the IRS uses that number to decide whether you have a gain or a loss.10Internal Revenue Service. Publication 551, Basis of Assets

The 3.8% Net Investment Income Tax

Higher earners face an extra 3.8% surtax on the lesser of their net investment income or the amount by which their modified adjusted gross income exceeds $200,000 (single) or $250,000 (married filing jointly).11Internal Revenue Service. Questions and Answers on the Net Investment Income Tax It reaches interest, dividends, capital gains, rental income, royalties, and passive business income. The thresholds do not adjust for inflation, so more taxpayers cross them every year.

Partnership, S Corp, and LLC Pass-Through Income

If you own part of a partnership, S corporation, or an LLC taxed as either one, the business itself usually pays no income tax. Your share of the profits flows through to your personal return on a Schedule K-1, and you owe tax on it whether or not the cash was actually distributed. The character of each item survives the flow-through: ordinary business income stays ordinary, capital gains stay capital, and qualified dividends keep their preferential rate.

One distinction catches new owners off guard. S corporation income on a K-1 is not subject to self-employment tax, while partnership income generally is. That gap is one reason people pick one entity over another. The tradeoff is that S corporation owners who work in the business must pay themselves a reasonable salary, and that salary carries full payroll taxes.

Rental Property and Royalty Payments

Rent from tenants is taxable, and the IRS defines rent broadly. Monthly checks count, but so do advance rent, security deposits you keep because the tenant broke the lease or damaged the unit, and the fair market value of services a tenant performs in place of paying cash.12Internal Revenue Service. Topic No. 414, Rental Income and Expenses Rental income and expenses go on Schedule E.13Internal Revenue Service. About Schedule E (Form 1040), Supplemental Income and Loss

Rental expenses are deductible against rental income. Mortgage interest, property taxes, insurance, repairs, and depreciation all reduce what you owe. Residential rental buildings are depreciated over 27.5 years on the straight-line method (land is not depreciable).14Internal Revenue Service. Publication 527, Residential Rental Property Depreciation often creates a paper loss even on a property with positive cash flow, but rental losses are considered passive and generally cannot offset wages or business income. If you actively manage the property and your AGI is $100,000 or less, you can deduct up to $25,000 in rental losses against other income. That allowance phases out completely at an AGI of $150,000.15Internal Revenue Service. Instructions for Form 8582, Passive Activity Loss Limitations

Royalties follow a similar pattern but involve intangible property or natural resources instead of real estate. Payments for licensing a patent, publishing your book, or letting a company extract oil or minerals from your land are royalties. They go on Schedule E and can be subject to the net investment income tax for higher earners.

Retirement Account Distributions

Money that leaves a retirement account is generally taxable in the year you receive it, because the contributions or the earnings got a tax break on the way in. Withdrawals from a traditional 401(k) or traditional IRA are taxed as ordinary income at your current rate.16Internal Revenue Service. Retirement Topics – Designated Roth Account The 2026 employee contribution limit for a 401(k) is $24,500, with an $8,000 catch-up for workers 50 and older and $11,250 for those aged 60 through 63.17Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026, IRA Limit Increases to $7,500

Roth accounts work in reverse. Contributions go in after tax, but qualified distributions come out completely tax-free. To qualify, the account must be at least five years old and you must be 59½ or older, disabled, or deceased.16Internal Revenue Service. Retirement Topics – Designated Roth Account

Employer pensions and annuities also count as ordinary income to the extent they represent previously untaxed contributions and earnings. Annuities convert a lump sum into a stream of payments, and the taxable portion of each payment depends on the ratio of your after-tax investment to the expected total payout.

Early Withdrawals and Required Minimum Distributions

Pulling money out before age 59½ triggers a 10% penalty on top of regular income tax.18Internal Revenue Service. Retirement Topics – Exceptions to Tax on Early Distributions Exceptions exist for permanent disability, qualified education expenses, and a first home purchase (up to $10,000 from an IRA), but the income tax on the withdrawal generally still applies.

You cannot leave money in a traditional account forever either. Required minimum distributions must start by April 1 of the year after you turn 73. Miss one and the penalty is 25% of what you should have taken, dropping to 10% if you fix the shortfall within the IRS correction window.19Internal Revenue Service. Publication 590-B, Distributions from Individual Retirement Arrangements Roth IRAs carry no required distributions during the owner’s lifetime.

Social Security, Unemployment, and Workers’ Comp

Social Security benefits are partly taxable depending on how much other income you have. If your combined income (adjusted gross income plus nontaxable interest plus half your Social Security) exceeds $25,000 as a single filer or $32,000 as a married couple filing jointly, up to 50% of your benefits become taxable. Above $34,000 (single) or $44,000 (married filing jointly), up to 85% is taxable.20Internal Revenue Service. IRS Reminds Taxpayers Their Social Security Benefits May Be Taxable These thresholds have never been adjusted for inflation.

Unemployment compensation is fully taxable at the federal level. You can elect to have taxes withheld as payments arrive so nothing surprises you in April.21Internal Revenue Service. Unemployment Compensation

Workers’ compensation is different. Payments received for a workplace injury or illness under a workers’ compensation law are excluded from gross income entirely.22Internal Revenue Service. Publication 525, Taxable and Nontaxable Income Supplemental Security Income and Temporary Assistance for Needy Families payments are also not taxable.23Social Security Administration. SSI Eligibility Requirements

Alimony and Child Support

The tax treatment of alimony flipped for agreements finalized after 2018. If your divorce or separation agreement was executed after December 31, 2018, alimony is neither deductible by the payer nor taxable to the recipient.24Internal Revenue Service. Publication 504, Divorced or Separated Individuals Older agreements still governed by pre-2019 rules keep the old treatment (deductible to the payer, taxable to the recipient) unless the agreement was later modified to adopt the new rule.

Child support has always been tax-neutral. The paying parent gets no deduction, and the receiving parent owes no tax on it.24Internal Revenue Service. Publication 504, Divorced or Separated Individuals

Gambling Winnings, Jury Pay, Prizes, and Barter

Several income sources people overlook are fully taxable:

  • Gambling income is taxable regardless of the amount. For 2026, casinos and other payers issue Form W-2G when winnings reach $2,000 or more, with the exact threshold varying by game. Withholding is required when winnings minus the wager exceed $5,000.
  • Jury duty stipends are taxable and reported on Schedule 1. If your employer keeps paying your salary while you serve and you hand the jury pay over to them, you can deduct the amount returned as an adjustment to income.22Internal Revenue Service. Publication 525, Taxable and Nontaxable Income
  • Found money and treasure trove are gross income in the year you take possession. Contest prizes, lottery winnings, and awards follow the same rule.25eCFR. 26 CFR 1.61-14 – Miscellaneous Items of Gross Income
  • Bartering counts too. If you exchange services or goods instead of using cash, the fair market value of what you receive is taxable income.

Any accession to wealth is presumed taxable unless Congress specifically excluded it. When in doubt, report it.

Income That Federal Law Excludes

A handful of common receipts never appear on your return at all:

The recipient’s tax status is what controls. A cash gift from a relative is tax-free to you no matter how large, though the giver may owe gift tax or need to file a return above the annual exclusion.

What Happens If You Don’t Report Income

The IRS imposes a 20% accuracy-related penalty on underpayments caused by negligence or a substantial understatement of income.30Internal Revenue Service. Notice 746, Information About Your Notice, Penalty and Interest A 75% fraud penalty applies when the underreporting is intentional, and willful evasion is a federal crime. Interest on unpaid tax compounds daily, so a modest oversight can grow quickly. Reporting everything and letting the exclusions do their work is safer than hoping the IRS misses it.

State Income Taxes Sit on Top

Federal tax is only part of the picture. Most states tax many of the same categories, with top marginal rates ranging from about 2.5% to over 13%. Eight states impose no individual income tax at all, and a few tax only specific types of income such as interest and dividends. Because state rules on deductions, credits, and exemptions differ widely, the effective tax on any given income source depends heavily on where you live.