How to File Quarterly Estimated Taxes as a New Optometry Practice
Learn the step-by-step process for filing quarterly estimated taxes as a new optometry practice, including deadlines, calculations, and payment methods.
If you own a new optometry practice, you are likely considered self-employed or a pass-through entity owner, which means you must pay taxes on income as you earn it. The IRS requires quarterly estimated tax payments to cover income tax and self-employment tax (Social Security and Medicare). Missing these payments can lead to penalties and interest. This guide walks you through the exact steps to calculate, file, and pay your quarterly estimated taxes, with practical advice for 2026.
Understand Your Tax Obligations
As a new practice owner, you are responsible for paying:
- Income tax: Federal and possibly state income tax on your net profit.
- Self-employment tax: 15.3% of your net earnings (12.4% for Social Security, 2.9% for Medicare) up to the Social Security wage base, which is $176,100 for 2026. The additional Medicare tax of 0.9% applies if your income exceeds $200,000 (single) or $250,000 (married filing jointly).
If you form an S-corp, you may pay yourself a reasonable salary and pay payroll taxes, but you still need estimated payments for your share of profits. For a sole proprietorship, LLC, or partnership, you pay self-employment tax on all net income.
Know the Quarterly Deadlines for 2026
The IRS sets four payment due dates each year. For 2026, the deadlines are:
- 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
If a due date falls on a weekend or holiday, the deadline moves to the next business day. Mark these dates on your calendar and set reminders two weeks ahead.
Calculate Your Estimated Tax
You have two main methods to calculate your estimated tax:
Method 1: Annualized Income Installment Method
This method is more accurate if your income varies throughout the year. You calculate your tax based on your actual income for each period, then pay the difference. It requires Form 2210 (Underpayment of Estimated Tax by Individuals, Estates, and Trusts) and can be complex. Most new practices start with the regular method.
Method 2: Regular Installment Method (Simpler)
- Estimate your total net profit for the year. For a new practice, use your business plan, current revenue, and expenses. For example, if you expect $120,000 in net profit, that’s your starting point.
- Subtract deductions such as the qualified business income deduction (up to 20% of net profit), retirement contributions, and health insurance premiums.
- Calculate your taxable income and use the tax tables to estimate your income tax.
- Add self-employment tax: Multiply your net profit by 92.35% (to account for the deduction for one-half of self-employment tax), then apply 15.3%.
- Subtract any credits and add any other taxes (like additional Medicare tax).
- Divide by 4 to get your quarterly payment.
Example: If your estimated annual tax is $20,000, each quarterly payment is $5,000.
Safe Harbor Rule
To avoid penalties, you must pay at least 100% of your previous year’s tax liability (or 110% if your adjusted gross income was over $150,000). For a new practice, you may not have a prior year, so you must pay at least 90% of your current year’s liability. If your income is steady, use the safe harbor to avoid underpayment penalties.
Step-by-Step: How to File and Pay
Follow these steps to file your quarterly estimated taxes:
- Gather your financials: Track your revenue and expenses monthly. Use accounting software like QuickBooks or Xero to simplify.
- Calculate your estimated tax using the method above. You can use IRS Form 1040-ES (Estimated Tax for Individuals) which includes a worksheet.
- Choose a payment method:
- IRS Direct Pay: Free, online, and allows you to schedule payments up to 30 days in advance.
- Electronic Federal Tax Payment System (EFTPS): Free, requires enrollment, and offers history tracking.
- Credit/debit card: Convenient but charges a processing fee (around 1.87% to 2.5%).
- Check or money order: Mail with Form 1040-ES voucher, but slower and risk of loss.
- Make your payment by the deadline. For state taxes, check your state’s department of revenue for similar deadlines and payment portals.
- Keep records: Save confirmation numbers and screenshots for your tax files.
Common Mistakes to Avoid
- Underpaying: Pay at least the safe harbor amount to avoid penalties. The IRS charges a penalty based on the federal short-term rate plus 3%.
- Ignoring state taxes: Most states require quarterly estimated payments as well. Check your state’s rules.
- Mixing personal and business expenses: Keep separate accounts to simplify tracking.
- Forgetting to adjust: If your income changes significantly, recalculate and adjust your next payment.
Frequently Asked Questions
What if I miss a quarterly deadline?
You can still make the payment late, but you may owe a penalty. The penalty is based on the amount due and the number of days late. File Form 2210 to see if you qualify for a waiver.
Can I pay estimated taxes with a credit card?
Yes, but the IRS charges a processing fee. For example, a $5,000 payment might cost $93.50 to $125 in fees. Weigh the cost against rewards or cash flow needs.
Do I need to file a separate return for estimated taxes?
No, you file Form 1040-ES only to pay. Your annual tax return (Form 1040) reconciles your payments.
How do I handle estimated taxes if I have an S-corp?
If you are an S-corp owner, you must pay yourself a reasonable salary and withhold payroll taxes. For your share of profits, you may need to make estimated payments. Consult a CPA to ensure compliance.
The Bottom Line
Filing quarterly estimated taxes is a non-negotiable part of owning a new optometry practice. Start by calculating your expected tax liability, use the safe harbor rule to avoid penalties, and set up automatic payments through IRS Direct Pay or EFTPS. Track your income monthly and adjust payments as needed. If you’re unsure, invest in a CPA who specializes in small practices; the cost (typically $300-$500 for a consultation) is worth the peace of mind. By staying on top of these deadlines, you’ll avoid IRS headaches and keep your practice financially healthy.