What Are Quarterly Estimated Taxes?
Quarterly estimated taxes are periodic payments made to the IRS to cover income tax and self-employment tax on earnings that aren't subject to withholding. The U.S. tax system operates on a pay-as-you-go basis, which means taxes are owed as income is earned throughout the year.
For small business owners, this typically includes income earned through sole proprietorships, partnerships, S corporations, and single-member LLCs. If your business structure means no employer is withholding taxes on your behalf, the responsibility to make quarterly tax payments for small business falls squarely on your shoulders.
Self-employment quarterly taxes cover both the income tax you owe and the self-employment tax, which accounts for your share of Social Security and Medicare contributions. W-2 employees split these costs with their employer, but self-employed individuals pay both the employer and employee portions.
Who Needs to Make Estimated Tax Payments?
Not every small business owner is required to make estimated tax payments, but most are. According to IRS estimated tax requirements, you generally must make quarterly payments if both of the following conditions apply:
- You expect to owe at least $1,000 in federal tax for the current year after subtracting withholding and refundable credits.
- Your withholding and refundable credits will cover less than the smaller of: 90% of the tax you'll owe for the current year, or 100% of the tax shown on your prior year's return (this threshold increases to 110% if your adjusted gross income exceeded $150,000, or $75,000 if married filing separately).
Common Filers Who Make Quarterly Payments
Several types of earners frequently find themselves subject to these requirements:
- Sole proprietors and single-member LLC owners
- Partners in a business partnership
- S corporation shareholders who receive distributions
- Freelancers, independent contractors, and gig workers
- Individuals with significant investment income such as interest, dividends, or capital gains
- W-2 employees whose withholding doesn't fully cover their tax liability
If you had no tax liability in the prior year and were a U.S. citizen or resident for the full year, you may be exempt from making estimated payments for the current year. However, this exception applies to a relatively narrow group of taxpayers.
Read our blog about essential accounting practices for small businesses.
Understanding the Quarterly Tax Deadlines
One of the most important aspects of managing your small business quarterly taxes is knowing exactly when payments are due. Despite being called "quarterly," the IRS payment schedule doesn't align neatly with calendar quarters. The intervals between due dates are uneven, so it's critical to mark each one on your calendar.
For the 2026 tax year, the quarterly tax deadlines are as follows:
- First Quarter (January 1 – March 31): Payment due April 15, 2026
- Second Quarter (April 1 – May 31): Payment due June 15, 2026
- Third Quarter (June 1 – August 31): Payment due September 15, 2026
- Fourth Quarter (September 1 – December 31): Payment due January 15, 2027
If a due date falls on a weekend or federal holiday, the deadline shifts to the next business day. It's worth noting that the second "quarter" actually only covers two months of income, while the third covers three months. Planning around these uneven intervals can help you manage cash flow more effectively.
How to Calculate Estimated Taxes
Learning how to calculate estimated taxes is one of the most valuable skills a small business owner can develop. The IRS provides Form 1040-ES specifically for this purpose, and it includes a worksheet designed to walk you through the calculation step by step.
The Basic Calculation Process
Here's a simplified overview of how the process works:
- Estimate your expected adjusted gross income for the year, including all business income, freelance earnings, investment income, and any other sources.
- Subtract your expected deductions, whether you plan to itemize or take the standard deduction. Don't forget above-the-line deductions like the deductible portion of self-employment tax and contributions to retirement accounts.
- Calculate your expected tax liability using the current year's tax brackets.
- Add self-employment tax. Remember that self-employment tax applies to 92.35% of your net self-employment income, and the combined rate covers both Social Security and Medicare.
- Subtract any expected credits and withholding from other income sources.
- Divide the remaining amount by four to determine each quarterly payment (or use the annualized income installment method if your income fluctuates significantly throughout the year).
Your prior year's tax return is an excellent starting point for these estimates. If your income and expenses remain relatively stable year over year, basing your payments on last year's numbers can simplify the process considerably.
The Safe Harbor Rule
The IRS offers what's commonly known as a "safe harbor" provision that can protect you from estimated tax penalties even if you end up owing additional tax when you file your return. You can generally avoid penalties by paying whichever is smaller:
- 90% of the tax you expect to owe for the current year, or
- 100% of the tax shown on your prior year's return (110% if your prior year adjusted gross income exceeded $150,000)
Many small business owners choose the prior-year safe harbor method because it provides certainty. You know exactly what last year's tax bill was, which makes calculating your quarterly payments straightforward.
Form 1040-ES: Your Quarterly Payment Tool
Form 1040-ES is the primary document used to calculate and submit your estimated tax payments. The form includes a detailed worksheet that guides you through estimating your income, deductions, credits, and resulting tax liability for the year.
You don't actually file Form 1040-ES with the IRS in the traditional sense. Instead, the worksheet helps you determine the correct payment amount, and the form includes payment vouchers you can use if you're mailing a check. However, the IRS strongly encourages electronic payment methods, which offer faster processing and immediate confirmation.
Payment Methods Available
The IRS provides several convenient ways to submit your quarterly tax payments for small business:
- IRS Direct Pay: A free service that lets you pay directly from your bank account with immediate confirmation.
- Electronic Federal Tax Payment System (EFTPS): A free, secure system operated by the U.S. Treasury that allows you to schedule payments in advance and maintain a detailed payment history. Enrollment is required.
- IRS2Go Mobile App: The official IRS mobile application allows you to make payments from your phone.
- Credit or Debit Card: Payments can be made through approved third-party processors, though processing fees apply.
- Check or Money Order: You can still mail payments using the vouchers included with Form 1040-ES, though electronic methods are preferred.
Setting up electronic payments early in the year rather than waiting until the first deadline approaches can save you significant stress and help you avoid processing delays during peak filing periods.
Common Mistakes Small Business Owners Make
Even well-intentioned business owners can stumble when it comes to managing their tax obligations. Being aware of the most common pitfalls can help you steer clear of costly errors.
Underestimating income is one of the most frequent issues, particularly for businesses experiencing growth. If your revenue is climbing compared to last year, relying solely on prior-year figures without adjusting upward can leave you short when tax time arrives.
Forgetting about self-employment tax is another common oversight. Many new business owners budget only for income tax and are surprised by the additional self-employment tax liability, which can add a significant amount to each quarterly payment.
Failing to track expenses properly throughout the year can also lead to miscalculated payments. Accurate bookkeeping ensures that your deductions are captured correctly, which directly affects how much you owe each quarter.
Finally, many small business owners simply miss deadlines because they don't have the dates firmly on their radar. Setting calendar reminders well in advance of each due date gives you time to prepare funds and submit your payment without rushing.
Read our blog about the importance of separating business and personal finances.
Frequently Asked Questions
What happens if I miss a quarterly estimated tax payment?
If you miss a quarterly tax deadline or underpay, the IRS may charge an estimated tax penalty plus interest on the underpaid amount. The penalty accrues from the original due date until the payment is made. However, you can still make the payment as soon as possible to minimize the penalty amount, and certain exceptions may apply depending on your circumstances.
Can I make more than four estimated tax payments per year?
Yes, you can make estimated tax payments as frequently as you'd like. Some business owners prefer to make monthly payments to spread the financial burden more evenly. As long as your total payments meet or exceed the required amount by each quarterly tax deadline, you'll satisfy the IRS estimated tax requirements.
Do I still need to file an annual tax return if I make quarterly payments?
Absolutely. Estimated tax payments are not a substitute for filing your annual tax return. When you file your return, you'll reconcile your actual tax liability against the payments you've made throughout the year. If you've overpaid, you can receive a refund or apply the credit to the following year's estimated payments. If you've underpaid, you'll owe the difference plus any applicable penalties.
How do I know if my estimated payments are accurate enough?
The safest approach is to use the safe harbor rules. If you pay at least 90% of your current year's tax liability or 100% of your prior year's tax (110% for higher earners), you'll generally avoid penalties. Reviewing your income and expenses at each quarterly interval allows you to adjust your payments if your financial situation changes.
What if my income varies significantly from quarter to quarter?
If your income is uneven throughout the year, you may benefit from the annualized income installment method. This approach lets you calculate your estimated tax based on income actually earned during each period rather than dividing an annual estimate into four equal parts. You'll need to complete Form 2210, Schedule AI, when filing your annual return to document this method.
Let Zera Accounting Help You Stay on Track
Navigating quarterly estimated taxes doesn't have to be overwhelming. At Zera Accounting, we've spent over 20 years helping small business owners understand their tax obligations and develop strategies to stay compliant while keeping more of their hard-earned money. From calculating your estimated tax payments to ensuring your accounting records are accurate and up to date, our experienced team is here to guide you through every step.
If you're unsure whether you need to make estimated payments, need help with Form 1040-ES, or want a trusted partner to manage your quarterly tax payments for small business, we'd love to hear from you. Contact us today to schedule a consultation and take the stress out of estimated taxes.