To file taxes for a single-member LLC, you report the business on Schedule C attached to your personal Form 1040, calculate Social Security and Medicare on Schedule SE, and, if you expect to owe $1,000 or more, send quarterly estimated payments using Form 1040-ES.1Internal Revenue Service. Estimated Taxes The IRS treats a domestic single-member LLC as a “disregarded entity” by default, so the LLC itself files nothing separately; all of its income and expenses flow onto your individual return.2Internal Revenue Service. Single Member Limited Liability Companies
What Disregarded Entity Status Means for Filing
The default classification sounds bureaucratic but the effect is straightforward: for federal income tax, the IRS acts as though the LLC does not exist as a separate taxpayer. Your business income is your income, your business deductions are your deductions, and everything lands on your Form 1040.2Internal Revenue Service. Single Member Limited Liability Companies The state still recognizes the LLC as a separate legal entity for liability purposes; the disregarded treatment is a tax label, not a legal one.
You use your Social Security Number on the return unless the business has employees or excise tax obligations, in which case you need an EIN.2Internal Revenue Service. Single Member Limited Liability Companies
The Forms You File and How They Connect
Four documents do most of the work, and each feeds the next.
Schedule C: Profit or Loss From Business
Schedule C is the core form. It asks for your name, taxpayer ID, business activity code, and accounting method, then walks through revenue and expenses.3Internal Revenue Service. About Schedule C (Form 1040), Profit or Loss From Business (Sole Proprietorship) Gross receipts go on Line 1. After cost of goods sold (if applicable) and any other business income, you have gross income. Part II lists expenses on Lines 8 through 27: advertising, rent, utilities, office supplies, insurance, and the rest. Subtracting total expenses from gross income produces the net profit or loss on Line 31.4Internal Revenue Service. 2025 Instructions for Schedule C (Form 1040)
Line 31 is the number the rest of your return depends on. It transfers to Schedule 1, Line 3, and becomes part of total income on your 1040.5Internal Revenue Service. Schedule 1 (Form 1040) 2025 A loss can offset other taxable income, though passive activity rules and at-risk limitations may cap how much you deduct in the year.
Schedule SE: Self-Employment Tax
Because no employer is withholding Social Security and Medicare from your business earnings, you owe both halves yourself. Schedule SE uses the Schedule C net profit to calculate a combined 15.3% rate: 12.4% for Social Security and 2.9% for Medicare.6Internal Revenue Service. 2025 Schedule SE (Form 1040) The Social Security portion applies only to the first $184,500 of net self-employment earnings for the 2026 tax year.7Social Security Administration. 2026 Cost-of-Living Adjustment (COLA) Fact Sheet The Medicare portion has no cap. Above $200,000 of net self-employment income ($250,000 married filing jointly), an additional 0.9% Medicare surtax applies to the excess.
The SE tax total lands on Schedule 2, and half of it comes back to you as an adjustment to income on Schedule 1, reducing your adjusted gross income for income tax purposes.6Internal Revenue Service. 2025 Schedule SE (Form 1040)
Form 1040 and Its Schedules
Your business income (from Schedule 1) and your self-employment tax (from Schedule 2) both meet up on Form 1040, along with everything else on your personal return: W-2 wages if you have any, investment income, credits, and withholding. The 1040 is where the final tax owed or refund is computed.
Records to Have Ready Before You Start
Before opening any forms, pull together:
- Your SSN, or the LLC’s EIN if you have one
- Gross receipts totals from bank statements, payment processors, and sales records
- Receipts and records for advertising, supplies, insurance, travel, contractor payments, and other business costs
- Mileage logs for any vehicle used for business, and utility bills or square footage for a home office
Keeping a running profit and loss statement through the year is far easier than rebuilding twelve months in March. The IRS requires you to retain these records for at least three years from the date the return was filed.8Internal Revenue Service. How Long Should I Keep Records
Quarterly Estimated Payments
Because nothing is withheld from your business income, the IRS wants payments through the year, not one lump sum in April. You are required to pay estimated taxes if you expect to owe $1,000 or more on the return.1Internal Revenue Service. Estimated Taxes Use the Form 1040-ES worksheets to estimate each installment, covering both income tax and self-employment tax.
The four installment dates for the 2026 tax year are:9IRS. 2026 Form 1040-ES – Estimated Tax for Individuals
- 1st payment: April 15, 2026
- 2nd payment: June 15, 2026
- 3rd payment: September 15, 2026
- 4th payment: January 15, 2027
You can skip the January 15 payment if you file the 2026 return by February 1, 2027, and pay the full balance with it.9IRS. 2026 Form 1040-ES – Estimated Tax for Individuals
To avoid an underpayment penalty, pay at least 90% of your current-year tax or 100% of last year’s tax, whichever is smaller. If your prior-year adjusted gross income was above $150,000 ($75,000 married filing separately), the prior-year safe harbor rises to 110%.10Internal Revenue Service. Underpayment of Estimated Tax by Individuals Penalty The prior-year test is often the easier target in your first profitable year, when the prior year’s tax may have been low.
Payments can go through the Electronic Federal Tax Payment System (EFTPS), IRS Direct Pay, or approved credit and debit card processors.
Annual Filing Deadline and Extensions
Form 1040 and its schedules are due April 15 of the year after the tax year. For 2026 income, that means April 15, 2027, with a shift to the next business day when the 15th falls on a weekend or federal holiday.
Filing Form 4868 by the April deadline gives you an automatic six-month extension to October 15. You can submit it electronically, on paper, or by making an electronic tax payment and marking it as an extension payment, which triggers the extension automatically.11Internal Revenue Service. Form 4868 – Application for Automatic Extension of Time To File U.S. Individual Income Tax Return An extension buys time to file, not time to pay. Interest runs on any unpaid balance from April 15 regardless of the extension, so estimate what you owe and send it with the extension.
Penalties for Filing or Paying Late
The IRS applies two separate penalties, and they can run at the same time.
The failure-to-file penalty is 5% of the unpaid tax for each month or partial month the return is late, up to 25%.12Internal Revenue Service. Failure to File Penalty The failure-to-pay penalty is 0.5% of the unpaid tax per month, also capping at 25%.13Internal Revenue Service. Topic No. 653, IRS Notices and Bills, Penalties and Interest Charges When both apply in the same month, the filing penalty is reduced by the payment penalty amount, so the combined monthly hit is 5%, not 5.5%. After the filing penalty maxes out at five months, the payment penalty keeps running on its own.
If you cannot do both, file on time. Filing (or extending) by April 15 removes the steeper 5% monthly charge and leaves only the 0.5% payment penalty plus interest.
Deductions That Reduce What You Owe
Half of Self-Employment Tax
Half of the SE tax calculated on Schedule SE comes off your income on Schedule 1 as an above-the-line deduction, lowering your adjusted gross income even though it does not shrink the SE tax itself.6Internal Revenue Service. 2025 Schedule SE (Form 1040)
Qualified Business Income Deduction
A single-member LLC treated as a disregarded entity may qualify for the Section 199A deduction, worth up to 20% of qualified business income. Originally set to expire after 2025, it was made permanent by the One Big Beautiful Bill Act, signed into law in 2025. The deduction reduces taxable income but does not reduce AGI or SE tax.
If your 2026 taxable income is below $201,750 (single) or $403,500 (married filing jointly), you generally get the full 20% without further limits. Above those thresholds the deduction phases out for service-based businesses like law, accounting, health care, and consulting, over a range of $75,000 for single filers and $150,000 for joint filers. Non-service businesses above the threshold face a separate limitation tied to W-2 wages paid and the value of qualified property. The deduction is capped at the lesser of 20% of qualified business income or 20% of taxable income before the QBI deduction.
Self-Employed Health Insurance
If you pay your own health insurance premiums, you can deduct medical, dental, and vision premiums for yourself, your spouse, your dependents, and any children under 27. The plan must be established under your business, though the policy can be in the business name or your own name. The deduction is calculated on Form 7206, reported on Schedule 1 Line 17, and cannot exceed the business’s net profit. You cannot claim it for any month you were eligible for a subsidized health plan through an employer, your spouse’s employer, or a parent’s employer.14Internal Revenue Service. Instructions for Form 7206 Because it is above the line, you get the benefit even if you take the standard deduction.
Should You Elect a Different Tax Status
The disregarded-entity default is not your only option. You can elect corporate tax treatment by filing Form 8832.2Internal Revenue Service. Single Member Limited Liability Companies More commonly, owners with strong profits elect S-corporation treatment by filing Form 2553. The election must be filed no more than two months and 15 days after the start of the tax year it is to take effect, or at any time during the preceding tax year.15Internal Revenue Service. Instructions for Form 2553 For a calendar-year LLC that means March 15 of the year the election applies.
S-corp treatment can lower self-employment tax: you pay yourself a reasonable salary subject to payroll taxes, and remaining profit distributed to you is not subject to those additional taxes. The IRS scrutinizes whether the salary is reasonable for the work performed, and the election adds payroll filings and cost, so it pays off only when profits comfortably exceed a reasonable salary.
State Taxes and Reports Are Separate
Federal filing is only part of what a single-member LLC owes. Most states tax business profits through their own income tax, and many require an annual report or franchise tax to keep the LLC in good standing. Fees and deadlines vary widely and rarely match the federal calendar. Missing a state filing can trigger administrative dissolution, which strips the liability protection the LLC was formed to give you. Check your state’s secretary of state and department of revenue for the specifics that apply to you.