How to File Quarterly Estimated Taxes as a New Aba Practice
Learn the step-by-step process for paying quarterly estimated taxes as a new ABA practice, including deadlines, calculations, and penalties to avoid.
As a new ABA (Applied Behavior Analysis) practice owner, you’re likely used to managing clinical care, not tax paperwork. But once you start earning income as a sole proprietor, LLC, or S-corp, the IRS expects you to pay taxes on that income throughout the year, not just in April. Quarterly estimated taxes are how you do that. This guide walks you through exactly how to calculate, file, and pay them, so you can avoid penalties and stay on the IRS’s good side.
Who Needs to Pay Quarterly Estimated Taxes?
If you expect to owe at least $1,000 in federal taxes for the year (after withholding and credits), you generally need to make estimated tax payments. This applies to:
- Sole proprietors (including single-member LLCs)
- Partners in a partnership
- S-corp shareholders who receive distributions
- C-corp owners who don’t have enough withholding
For a new ABA practice, you likely fall into one of these categories. Even if you’re an S-corp and pay yourself a salary, the payroll withholding may not cover your full tax liability, especially if you take distributions.
When Are Quarterly Estimated Taxes Due?
The IRS sets four payment deadlines each year. For the 2026 tax year, the due dates are:
| Quarter | Payment Period | Due Date |
|---|---|---|
| Q1 | Jan 1 - Mar 31 | April 15, 2026 |
| Q2 | Apr 1 - May 31 | June 15, 2026 |
| Q3 | Jun 1 - Aug 31 | September 15, 2026 |
| Q4 | Sep 1 - Dec 31 | January 15, 2027 |
Note: If a due date falls on a weekend or federal holiday, the deadline moves to the next business day. For example, if April 15 is a Saturday, you have until Monday, April 17.
How to Calculate Your Estimated Tax
Calculating estimated tax involves projecting your income, deductions, and credits for the year. Here’s a simplified method:
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Estimate your annual gross income from your ABA practice. Look at your current revenue and project forward. For example, if you’ve been open for 3 months and made $30,000, you might project $120,000 for the year.
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Subtract your business expenses. Common ABA practice expenses include: rent, utilities, clinical supplies (e.g., assessment tools, reinforcers), software (e.g., practice management, EHR), marketing, professional liability insurance, and payroll (if you have employees).
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Subtract your standard or itemized deductions. For 2026, the standard deduction is estimated at $15,000 for single filers and $30,000 for married filing jointly (these figures are adjusted annually for inflation, so confirm with the IRS).
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Calculate your taxable income and apply the appropriate tax rate. For 2026, the federal income tax brackets are estimated to be:
| Rate | Single Filer | Married Filing Jointly |
|---|---|---|
| 10% | $0 - $11,600 | $0 - $23,200 |
| 12% | $11,601 - $47,150 | $23,201 - $94,300 |
| 22% | $47,151 - $100,525 | $94,301 - $201,050 |
| 24% | $100,526 - $191,950 | $201,051 - $383,900 |
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Add self-employment tax. As a self-employed individual, you pay both the employee and employer portions of Social Security and Medicare, which totals 15.3% of your net earnings. This is in addition to income tax.
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Divide by 4 to get your quarterly payment amount.
Example: Suppose you’re a single filer with projected net income of $80,000 after expenses and deductions. Your income tax might be around $12,000, and self-employment tax around $12,240 (15.3% of $80,000). Total tax = $24,240. Quarterly payment = $6,060.
Safe Harbor Rule: A Simpler Alternative
If calculating your projected income feels overwhelming, you can use the safe harbor method. Pay 100% of the tax you owed last year (or 110% if your adjusted gross income was over $150,000). As a new practice, you may not have had a prior year, so this may not apply. But in subsequent years, it can simplify your payments.
How to Pay Your Quarterly Estimated Taxes
You have several payment options:
- IRS Direct Pay: Free, online, and allows you to pay directly from your bank account. You can schedule payments up to 30 days in advance.
- Electronic Federal Tax Payment System (EFTPS): Free, but requires enrollment. Good for business owners who want to schedule payments.
- Credit/debit card: Convenient, but the IRS charges a processing fee (around 1.85% to 2.9% of the payment).
- Mail a check: Include Form 1040-ES voucher. Slower and risk of postal delays, so use only if necessary.
For state estimated taxes, check your state’s department of revenue website. Most states have similar quarterly deadlines and online payment portals.
What Happens If You Miss a Payment?
If you underpay or miss a deadline, the IRS charges a penalty based on the amount owed and the number of days late. The penalty is essentially interest, and the rate is set quarterly (it was around 7% in 2025, but check the current rate). To avoid this, set calendar reminders and consider automatic payments.
How to Adjust Payments Throughout the Year
Your income may fluctuate as your ABA practice grows. You can adjust your quarterly payments by recalculating after each quarter. If you overpay, you’ll get a refund when you file your annual return. If you underpay, you may face penalties. The IRS allows you to annualize your income, which means you can pay based on actual income each quarter, but this requires Form 2210 and can be complex. Most new owners simply pay equal amounts each quarter based on their initial projection.
FAQ
Q: Do I need to pay quarterly taxes if I’m an S-corp? A: Yes, if you take distributions. You must pay yourself a reasonable salary, and payroll withholding covers some tax, but distributions are not subject to withholding. You’ll need to make estimated payments for the tax on those distributions.
Q: Can I pay estimated taxes with a credit card? A: Yes, but the IRS charges a processing fee. It might be worth it for the rewards, but the fee usually outweighs the benefits. Direct Pay is free and just as easy.
Q: What if I don’t pay quarterly taxes and just pay everything in April? A: You’ll likely face an underpayment penalty. The IRS expects taxes to be paid as you earn income. The penalty is calculated from the due date of each quarter, so it can add up.
Q: How do I know if my estimated payments are enough? A: Use the safe harbor rule: pay at least 100% of last year’s tax (or 110% if your AGI was over $150,000). If you’re new, aim to pay at least 90% of your current year’s tax liability to avoid penalties.
The Bottom Line
Quarterly estimated taxes are a non-negotiable part of running an ABA practice. By understanding who needs to pay, when payments are due, and how to calculate them, you can avoid penalties and keep your cash flow predictable. Start by projecting your income and expenses, set aside a percentage of every payment you receive, and mark the four due dates on your calendar. If you’re unsure about your numbers, consult a CPA who works with small business owners. Taking these steps now will save you stress and money come tax season.