Michelle Browne - 12/15/2025

Running a small business comes with many rewards, but it also brings unique financial responsibilities. One area that often catches new and seasoned entrepreneurs off guard is quarterly estimated taxes. Unlike employees who have taxes automatically withheld from each paycheck, business owners, freelancers, and independent contractors must calculate, budget, and pay taxes throughout the year.

If you’ve ever been surprised by a large tax bill at the end of the year, or if you’re unsure whether quarterly taxes apply to you, this guide will give you the clarity you need.

At Browne Bookkeeping Services, Inc., we help small business owners take control of their financial obligations so tax season doesn’t feel overwhelming. Here’s everything you need to know about quarterly taxes and how to manage them effectively.

What Are Quarterly Estimated Taxes?

Quarterly estimated taxes are payments made to the IRS and, in some cases, your state, four times per year. These payments cover both:

• Income tax – based on your business profits.
  
  

• Self-employment tax – which includes contributions to Social Security and Medicare.
  
  

In other words, quarterly taxes ensure you’re paying as you go, rather than waiting until the end of the year.

Pro Tip: Even if your business is new and you’re unsure about profitability, it’s better to estimate and pay something rather than risk underpayment penalties.

Who Is Required to Pay Quarterly Taxes?

You are generally required to pay quarterly estimated taxes if both of the following apply:

1. You expect to owe at least $1,000 in taxes when your annual return is filed.
   
   

2. You don’t have enough tax withheld through other income (for example, if you also work a W-2 job).
   
   

This includes:

• Sole proprietors and single-member LLCs
  
  

• Partnerships and multi-member LLCs
  
  

• S-Corporation shareholders
  
  

• Freelancers, consultants, and independent contractors
  
  

Even side hustlers with part-time self-employment income may need to file, depending on how much they earn.

When Are Quarterly Taxes Due?

The IRS sets four payment deadlines each year:

• 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
  
  

Missing a payment doesn’t just mean catching up later—it could also result in penalties and interest. That’s why consistent planning is key.

How to Calculate Quarterly Estimated Taxes

Figuring out your payments isn’t always straightforward, especially if your income fluctuates. Here are the steps most small business owners follow:

1. Estimate your total annual income.
   
   

2. Subtract business expenses to calculate net profit.
   
   

3. Apply federal tax rates and self-employment tax.
   
   

4. Factor in deductions, credits, and any taxes already withheld.
   
   

5. Divide the result by four for quarterly payments.
   
   

The IRS provides Form 1040-ES to help calculate estimated taxes, but for many business owners, the form feels more complicated than helpful. Bookkeeping software and professional support can simplify the process.

Common Mistakes to Avoid

Many small business owners make errors when handling quarterly taxes. Here are the top pitfalls to watch out for:

• Not setting aside money regularly. Waiting until payment deadlines can leave you scrambling.
  
  

• Ignoring fluctuating income. If your earnings change each quarter, your tax payments should, too.
  
  

• Overlooking deductions. Expenses like home office, mileage, and professional services reduce taxable income.
  
  

• Assuming “small” side income doesn’t matter. Even part-time earnings may trigger tax obligations.
  
  

Tips for Staying Ahead of Quarterly Taxes

1. Create a tax savings account. Automatically transfer a percentage of every payment you receive into a separate account.
   
   

2. Leverage bookkeeping software. Tools like QuickBooks can help track income and generate reports for tax planning.
   
   

3. Keep accurate records. Organized books mean fewer surprises and easier calculations.
   
   

4. Work with a professional. A bookkeeper or accountant can provide tailored advice and adjust your plan as your business grows.
   
   

How Browne Bookkeeping Services, Inc. Can Help

Managing quarterly taxes doesn’t have to feel overwhelming. At Browne Bookkeeping Services, Inc., we specialize in helping small business owners:

• Track income and expenses accurately year-round.
  
  

• Calculate estimated tax payments confidently.
  
  

• Stay ahead of IRS deadlines to avoid penalties.
  
  

• Plan strategically to minimize tax burdens and maximize deductions.
  
  

We don’t just help you file paperwork—we provide the clarity and structure that keeps your finances on track, so you can focus on running and growing your business.

Final Thoughts

Quarterly estimated taxes are an essential part of running a small business. By planning ahead, staying organized, and seeking professional support, you can avoid costly mistakes and keep your financial health strong all year long.

Ready to take the stress out of quarterly taxes? Contact Browne Bookkeeping Services, Inc. today and let our team guide you through every step.