Businesses pay taxes on several overlapping schedules across the year, not in a single annual payment. Federal income tax is paid in four estimated installments (April 15, June 15, September 15, and January 15 for pass-through owners and sole proprietors; the 4th, 6th, 9th, and 12th months for C corporations). Employers deposit payroll taxes monthly or semi-weekly depending on size, file W-2s and 1099-NECs by January 31, and remit FUTA quarterly once it exceeds $500. Annual returns are due March 15 for S corporations and partnerships and April 15 for sole proprietors and C corporations. State sales tax, property tax, and franchise tax run on their own calendars.
Which of these apply to you depends on your structure, whether you have employees, and what you sell.
Quarterly Estimated Income Tax
Federal tax is pay-as-you-go. If you expect to owe $1,000 or more after withholding and refundable credits, you owe estimated payments.1Internal Revenue Service. IRS FAQs – Estimated Tax for Individuals C corporations have a lower trigger: $500 or more in expected liability.2Internal Revenue Service. Underpayment of Estimated Tax by Corporations Penalty
Sole Proprietors, Partners, and S Corporation Shareholders
These owners calculate their payments on Form 1040-ES.3Internal Revenue Service. Estimated Taxes The four periods don’t split evenly into calendar quarters:
- April 15, for income earned January 1 through March 31.
- June 15, for income earned April 1 through May 31.
- September 15, for income earned June 1 through August 31.
- January 15 of the following year, for income earned September 1 through December 31.
If a due date falls on a weekend or federal holiday, it shifts to the next business day.4Internal Revenue Service. Estimated Tax FAQ for Individuals
These payments cover both income tax and self-employment tax. Sole proprietors and partners owe self-employment tax at a combined 15.3% — 12.4% for Social Security on earnings up to $184,500 in 2026 and 2.9% for Medicare on all net earnings.5Internal Revenue Service. Self-Employment Tax (Social Security and Medicare Taxes)6Social Security Administration. Contribution and Benefit Base It’s calculated on Schedule SE and folded into what you send each quarter.
C Corporations
C corporation estimated payments are due in the 4th, 6th, 9th, and 12th months of the tax year. For a calendar-year corporation, the fourth payment falls on December 15 rather than January 15.7Internal Revenue Service. Publication 509 (2026), Tax Calendars That puts two payments about three months apart in September and December.
The Safe Harbor
You avoid underpayment penalties by paying either 90% of what you owe for the current year or 100% of what you owed last year. If your prior-year adjusted gross income exceeded $150,000 ($75,000 if married filing separately), the prior-year safe harbor rises to 110%.1Internal Revenue Service. IRS FAQs – Estimated Tax for Individuals For owners with uneven income, the prior-year figure is often the easier target because it’s already known.
Miss the mark and the IRS charges interest at the federal short-term rate plus three percentage points on the underpaid amount for the period it went unpaid.8Internal Revenue Service. Quarterly Interest Rates
State estimated tax often mirrors the federal schedule but not always. Check your state revenue department’s dates and thresholds.
Payroll Tax Deposits
Once you have an employee, you withhold federal income tax and the employee share of Social Security and Medicare from each paycheck, and pay the employer match on top. All federal payroll deposits must be made electronically.9Internal Revenue Service. Depositing and Reporting Employment Taxes
The IRS assigns you a deposit schedule based on your reported liability during a lookback period ending the prior June 30.10Internal Revenue Service. Topic No. 757, Forms 941 and 944 – Deposit Requirements
Monthly Schedule
If your lookback liability was $50,000 or less, you’re a monthly depositor. Taxes accumulated during a month are due by the 15th of the following month. New businesses with no lookback history default to monthly for the first year.10Internal Revenue Service. Topic No. 757, Forms 941 and 944 – Deposit Requirements
Semi-Weekly Schedule
Over $50,000 in the lookback period puts you on the semi-weekly schedule, keyed to your payday:
- Wednesday, Thursday, or Friday paydays: deposit by the following Wednesday.
- Saturday, Sunday, Monday, or Tuesday paydays: deposit by the following Friday.10Internal Revenue Service. Topic No. 757, Forms 941 and 944 – Deposit Requirements
The $100,000 Next-Day Rule
If your accumulated payroll tax liability reaches $100,000 or more on any single day, you must deposit the full amount by the next business day, whatever your normal schedule.11eCFR. 26 CFR 31.6302-1 – Deposit Rules for Taxes Under the Federal Insurance Contributions Act (FICA) and Withheld Income Taxes Hitting the threshold also moves you to semi-weekly status for the rest of that calendar year and all of the next.
FUTA
Federal unemployment tax runs on its own schedule. It’s reported annually on Form 940, due January 31 of the following year. But if your cumulative FUTA liability exceeds $500 in a quarter, you must deposit it by the end of the month after that quarter closes:12Internal Revenue Service. Instructions for Form 940 (2025)
- First quarter: deposit by April 30.
- Second quarter: deposit by July 31.
- Third quarter: deposit by October 31.
- Fourth quarter: deposit by January 31.
Liability of $500 or less in a quarter rolls forward until the cumulative amount crosses the threshold.12Internal Revenue Service. Instructions for Form 940 (2025) State unemployment tax follows its own schedule and rate, set by each state.
W-2 and 1099 Filings on January 31
If you paid employees or independent contractors, the annual information returns are due January 31. By that date, employees must receive Form W-2 and copies go to the Social Security Administration. Any independent contractor you paid $600 or more during the year gets a Form 1099-NEC, and copies are filed with the IRS.13Internal Revenue Service. Instructions for Forms 1099-MISC and 1099-NEC (04/2025) When January 31 lands on a weekend the deadline shifts; for the 2025 tax year it moves to February 2, 2026.14Internal Revenue Service. General Instructions for Certain Information Returns (2025)
Late information returns carry per-form penalties starting at $60 and rising to $340 or more per form the longer they’re delayed.15Internal Revenue Service. Information Return Penalties With even a modest contractor roster the totals mount quickly.
Sales and Use Tax
Sales tax is set entirely by your state. When you register for a permit, the state assigns a filing frequency based on expected sales volume, and adjusts it as your actual collections come in. High-volume sellers usually file monthly. Small and mid-size businesses more commonly file quarterly. Very low volume can qualify for annual filing.
Quarterly deadlines typically fall about a month after the calendar quarter ends, but exact dates vary. These are independent of the federal calendar.
Use tax applies to items you bought without paying sales tax — typically from out-of-state vendors — and then stored or used in your state. It generally follows the same filing frequency the state assigned for sales tax.
Annual Returns: March 15 or April 15
The annual return reconciles the year: actual income, deductions, credits, and what you already paid in. The deadline depends on your entity.
March 15: S Corporations and Partnerships
Calendar-year S corporations file Form 1120-S and partnerships file Form 1065, both due March 15. Neither entity pays income tax itself; the return produces Schedule K-1s that pass income through to owners’ personal returns. The March deadline exists so owners have their K-1s in hand before their own April 15 filing.
Form 7004 buys an automatic six-month extension to September 15.16Internal Revenue Service. About Form 7004, Application for Automatic Extension of Time to File Certain Business Income Tax, Information, and Other Returns Extending the entity return often forces owners to extend their personal returns too, because the K-1s arrive later.
April 15: Sole Proprietors and C Corporations
Sole proprietors report on Schedule C with their Form 1040, due April 15.17Internal Revenue Service. About Schedule C (Form 1040)18Internal Revenue Service. About Form 1120, U.S. Corporation Income Tax Return19Internal Revenue Service. Instructions for Form 700420Internal Revenue Service. Get an Extension to File Your Tax Return
The Payment Deadline Doesn’t Move
An extension buys time to file, not time to pay. Any balance owed is still due by the original March 15 or April 15 date. Underpayment triggers a failure-to-pay penalty of 0.5% per month on the unpaid balance, up to 25%, running from the original due date even when the extension itself was filed on time.21Internal Revenue Service. Failure to Pay Penalty Interest accrues on top.
Other Recurring Obligations
Property tax on real estate and business equipment is assessed by county or municipal governments, typically annually or semi-annually on dates set locally.
Excise tax applies to specific goods and activities — fuel, alcohol, tobacco, certain manufacturing. Filing frequency depends on the specific tax and volume, ranging from monthly to annually.
Many states charge a franchise tax or annual report fee to keep your entity in good standing. The due date is often tied to the anniversary of incorporation or a fixed statutory date. Missing it isn’t only a penalty issue: some states administratively dissolve the entity for non-payment, which can strip owners of the liability shield they relied on.