Quarterly estimated taxes are one of the first things that surprise new business owners. You spend months building your business, and then the IRS sends you a penalty notice ? not because you did anything wrong, but because nobody told you about estimated payments. This guide explains exactly what quarterly estimated taxes are, who owes them, how to calculate the amount, and how to avoid the most common mistakes.
What Are Quarterly Estimated Taxes?
When you work as an employee, your employer withholds income tax from every paycheck. As a self-employed person or business owner, no one does that for you. The IRS expects you to pay taxes as you earn income ? not just at year-end. Those periodic payments are called quarterly estimated taxes.
They cover two things: your federal income tax and your self-employment tax (which replaces the Social Security and Medicare withholding your employer used to handle).
Who Has to Pay Estimated Taxes?
You must make quarterly estimated tax payments if you expect to owe at least $1,000 in federal taxes after subtracting any withholding and credits. This applies to:
- Sole proprietors and single-member LLCs
- Partners in a partnership
- S-corporation shareholders who receive distributions
- Freelancers, consultants, and gig workers
- Landlords with significant rental income
Even if you have a day job with withholding, you may owe estimates if your side income pushes you over the threshold.
The Quarterly Estimated Tax Deadlines
Despite the name, the payment schedule is not perfectly quarterly. The IRS due dates are:
- April 15 ? covers January 1 through March 31
- June 15 ? covers April 1 through May 31
- September 15 ? covers June 1 through August 31
- January 15 (following year) ? covers September 1 through December 31
When a due date falls on a weekend or federal holiday, it moves to the next business day. Mark all four in your calendar at the start of each year.
How to Calculate Your Quarterly Estimated Tax Payment
There are two safe-harbor methods the IRS accepts:
Method 1: Pay 100% of Last Year’s Tax
If your prior-year adjusted gross income was $150,000 or less, you can pay 100% of what you owed last year across four equal installments and avoid any underpayment penalty ? even if your income grew significantly. (If AGI exceeded $150,000, you must pay 110% of last year’s tax.)
This is the simplest approach for stable businesses. Pull your prior-year Form 1040, find the total tax on line 24, divide by four, and pay that each quarter.
Method 2: Pay 90% of This Year’s Tax
Estimate your current-year taxable income, calculate the tax owed on it, multiply by 90%, and divide by four. This method works better when your income is declining or when you have large new deductions this year.
Quick Estimate for Most Service Businesses
A practical rule of thumb: set aside 25?30% of every payment you receive. Send 25% to the IRS each quarter and use what’s left to cover state taxes (if applicable) and keep a cushion. Florida has no state income tax, so Florida-based businesses only need the federal estimate.
How to Make the Payment
The IRS’s preferred payment method is the Electronic Federal Tax Payment System (EFTPS) at eftps.gov. You can also pay via IRS Direct Pay (no account required), mail a check with Form 1040-ES, or pay through your tax software. EFTPS lets you schedule all four payments at once at the start of the year ? useful if you’re disciplined about the safe-harbor amount.
What Happens If You Miss a Payment
The IRS charges an underpayment penalty calculated as a percentage of the shortfall for each day it’s late. The rate adjusts quarterly ? in recent years it’s been around 7?8% annualized. The penalty isn’t enormous, but it adds up, and it shows up as a surprise on your tax return when you were expecting a refund.
You can request a waiver (Form 2210) if you had unusual circumstances ? a major illness, a disaster, or income that came in unevenly late in the year.
State Estimates: Florida Is Different
Florida has no personal income tax, so sole proprietors and single-member LLCs in Florida don’t owe state estimated payments on their pass-through income. However, Florida C-corporations do pay Florida corporate income tax and must make quarterly state estimates.
Practical Tips from an Enrolled Agent
- Open a separate tax savings account. Move 25?30% of every deposit into it immediately. When estimates are due, the money is sitting there waiting.
- Use the prior-year safe harbor in year one. If last year you paid zero (because you were employed), you technically owe no estimates your first business year ? but start saving anyway so you’re not blindsided at year-end.
- Reconcile quarterly. At the end of each quarter, run a quick P&L. If income is running higher than expected, increase your next payment.
- Don’t confuse the payment date with the return date. Estimates are due in April, June, September, and January. Your annual return is due April 15 of the following year (or October 15 with an extension).
When Estimates Get Complicated
S-corporation owners have additional planning to do. If you’re paying yourself a reasonable salary, you can adjust your W-2 withholding to cover estimated taxes ? potentially eliminating quarterly payments altogether. Owners with significant investment income, rental income, or a mix of business structures should work through a projection with a tax professional rather than guessing.
As a Licensed Enrolled Agent, I help small business owners build quarterly tax routines that keep them penalty-free year after year. If you’re unsure what to pay this quarter, book a free call and we’ll work through it together.
