The June 15 Tax Payment That Sneaks Up on Practice Owners
If you own an optometry practice or work as a 1099 contract doctor, one date deserves a spot on your calendar right now: June 15. That is when your second-quarter estimated tax payment is due.
This is the payment that catches the most people off guard every single year. Not because it is complicated, but because of a quirk in how the IRS schedules it. Let's walk through why it sneaks up, how much you should be setting aside, and what actually happens if you slip and pay late.
Why Q2 Feels Like It Comes Out of Nowhere
Most people assume estimated taxes follow a clean three-month rhythm. They don't.
Here is the real schedule:
Q1 covers January through March. Three months. Due April 15.
Q2 covers only April and May. Two months. Due June 15.
Q3 covers June, July, and August. Three months. Due September 15.
Q4 covers September through December. Four months. Due January 15.
So Q2 gives you the shortest runway of the year. You just finished writing a check in mid-April, and barely two months later another one is due. That short gap is exactly why this payment slips through the cracks.
One quick note on the date itself. When a due date lands on a weekend or a federal holiday, the deadline generally rolls to the next business day. For 2026, June 15 falls on a normal business day, so that is your real date.
The fix is simple. Mark June 15 now, and build a habit of setting money aside as you earn it rather than scrambling when the deadline lands.
The Simple System: Save as You Go
The cleanest way to never feel squeezed by a tax deadline is to stop treating taxes as a quarterly event and start treating them as a daily one.
Open a separate savings account that you only touch for taxes. Then, as profit comes in, move a set percentage into that account automatically. When the quarterly deadline arrives, the money is already sitting there waiting. No scramble, no surprise, no raiding your operating account.
The only question left is what percentage to move. That depends on two things: federal and state.
How Much to Set Aside for Federal
Start with 25 percent of your net profit for federal. For most practice owners at a normal income level, that is a solid baseline.
Before the ranges, one important caveat. These are planning ranges, not exact tax calculations. Your real number depends on your total household income, your deductions, your spouse's income, how much your W-2 withholding already covers, your retirement contributions, your QBI deduction, and other items on your return. Treat the tiers below as a smart starting point, then let your CPA dial in the precise figure.
With that said, here is a practical guide based on your practice's annual net income, assuming you file a joint return:
Up to about $200,000: set aside 25 percent for federal
About $200,000 to $400,000: move up to 28 to 30 percent
Above about $400,000: plan on 32 to 35 percent
Part of the reason the percentage climbs is the 20 percent qualified business income deduction, usually called QBI. This is one of the bigger breaks pass-through owners get, but it phases out as income rises. Two things are worth understanding about it.
First, the limit is based on your taxable income before the QBI deduction, not simply your practice's net profit. Your other income, your spouse's income, and your deductions all feed into the number that matters.
Second, optometry is affected more directly than many businesses. Because optometry is generally treated as a health care field, it usually falls into what the IRS calls a specified service trade or business, the same category as physicians, dentists, pharmacists, and similar health professionals. For those businesses, the QBI deduction phases out completely once income climbs high enough.
For 2026, that phase-out begins at $403,500 of taxable income for married filing jointly and about $201,750 for most other filers. It finishes phasing out completely at $553,500 for joint filers and $276,750 for others. As you move through that range, more of every dollar becomes fully taxable, which is exactly why your set-aside should rise with your income.
(Note: The One Big Beautiful Bill Act, signed in July 2025, made the QBI deduction permanent. It is no longer scheduled to expire, and the figures here reflect the 2026 rules.)
A couple of adjustments to keep in mind. If you file single rather than jointly, you will reach each tier at roughly half those income levels. And if you have a high-earning spouse or take a large salary on top of your practice income, bump yourself up a tier.
How Much to Set Aside for State
State income tax is separate, and it lands on top of your federal set-aside. Plan on anywhere from 0 to 10 percent, depending entirely on where you practice.
No income tax states like Texas, Florida, Nevada, and Washington: add nothing for state income tax
Most states: add roughly 3 to 6 percent
High tax states like California, New York, and Oregon: add closer to 8 to 10 percent
Put the two together and a typical practice owner is moving somewhere between 28 and 45 percent of profit into savings. A higher earner in a high-tax state lands at the top of that range.
A Real Example for Practice Owners
Let's make this concrete with an S-corp owner, since that is how most established practices are structured.
Say your practice netted $10,000 in profit in April and $15,000 in May. That is $25,000 of pass-through profit for the quarter that flows to your personal return.
You also paid yourself $10,000 a month in W-2 wages. If your payroll withholding is set up correctly, it may already cover the tax on those wages. But do not assume it covers everything. Your estimated tax is ultimately based on your total personal tax liability for the year minus what your withholding actually pays in. A low W-4 setting, a spouse's income, a bonus, or other income outside the practice can all create a shortfall that withholding alone will not catch.
For this example, we will focus on the $25,000 of pass-through profit, since that is the piece your paycheck withholding clearly does not cover.
At 25 percent for federal, that is $6,250. Then add your state on top, anywhere from $0 in a no-tax state up to about $2,500 in a high-tax state. So your Q2 payment lands somewhere between $6,250 and $8,750.
That is the basic shape of the calculation. Profit times your set-aside percentage, with your CPA confirming the final number against your full return.
A Note for 1099 Contract Doctors
If you work as a 1099 contractor rather than an owner with payroll, your situation is different in one important way. Nobody is withholding anything for you.
When you are an employee, taxes come out of every paycheck automatically. As a 1099 doctor, that does not happen. The full burden of both your income tax and your self-employment tax falls on these quarterly estimated payments. There is no payroll system quietly covering it for you.
That self-employment tax is the piece people forget. The rate is 15.3 percent, but it generally applies to 92.35 percent of your net self-employment earnings rather than the full amount, so the effective bite is a little lower than the headline number suggests. There are also limits tied to the Social Security wage base and separate Medicare rules at higher income, which your CPA will factor in. Either way, it sits on top of your regular income tax and covers the Social Security and Medicare an employer would normally split with you. Because you are both the employer and the employee in the eyes of the IRS, you carry the whole thing.
So your set-aside needs to run higher than an owner's. Here is a practical starting point for a 1099 doctor:
Start at 30 percent for federal, which blends your income tax and self-employment tax
Scale up to 35 percent as your income climbs
Add 0 to 10 percent for state on top, same as everyone else
Quick example. Say you earned $25,000 in net 1099 income across April and May. At 30 percent for federal, you would set aside $7,500, plus your state amount. That higher percentage compared to the practice owner above is the self-employment tax doing its work.
The big takeaway for 1099 doctors: because you have zero withholding, these quarterly payments are not optional padding. They are the entire mechanism by which your taxes get paid. Skipping them is how people end up with a frightening balance and a penalty at filing time.
What Happens If You Pay Late
Let's clear up the fear here, because it is usually worse in people's heads than in reality.
This charge has a name. It is the underpayment of estimated tax penalty. The IRS calculates it much like interest, using a rate set each quarter based on the federal short-term rate. The penalty is computed using IRS underpayment rates, and unpaid balances can accrue IRS interest daily. For 2026, that rate started at 7 percent in the first quarter and dropped to 6 percent for the second.
Go back to the practice owner example. On the $6,250 federal payment, being one month late costs only about $30, depending on the exact number of days it sits unpaid.
So one late payment is not a catastrophe. It is worth keeping that in perspective so you do not panic.
But here is the real risk, and it is not the single $30. It is the habit. A small penalty is easy to shrug off once. Then it happens again the next quarter, and the next, and the misses stack up across the whole year. That is when it actually starts to cost real money, and worse, that is when you end up with a large unpaid balance and an unpleasant surprise at tax time.
The penalty is small. The pattern is expensive.
How to Avoid the Penalty Entirely
There is a clean way to take the penalty off the table completely. It is called the safe harbor, and you meet it by paying in at least one of these amounts across the year:
90 percent of your current year's total tax, or
100 percent of last year's total tax (110 percent if your prior-year Adjusted Gross Income (AGI) was above $150,000, or $75,000 if married filing separately).
If your payments and withholding add up to one of those thresholds, the IRS generally cannot charge you an underpayment penalty, even if you end up owing more at filing. One more bit of relief: if your total balance due for the year comes in under $1,000 after withholding and credits, there is no penalty at all.
For most owners, the simplest path is the prior-year safe harbor. You know exactly what you owed last year, so you know exactly what to pay this year to stay protected.
How to Actually Make the Payment
When June 15 arrives, paying is straightforward.
For federal, log into your personal account at IRS.gov. Make sure you are using your individual account, not a business account, since estimated payments for both practice owners and 1099 doctors flow through your personal return. From there, make a payment directly from your bank account.
A best-practice note for S-corp owners. Your personal estimated taxes should generally be paid from your personal account, not the business. If the cash you need is sitting in the business, that is completely fine. Just take a shareholder distribution to yourself first, then make the payment personally. That keeps a personal tax payment from accidentally getting recorded as a business tax expense, which would muddy both your books and your deductions.
The one step people get wrong is the selection. When you set up the payment, choose tax year 2026 and select estimated tax payment as the reason. That tells the IRS to apply the money to the right year and the right bucket. Pick the wrong year or category and your payment can land in the wrong place, which is a headache to untangle later.
For state, search for your state's department of revenue online payment portal. Most states have a simple system that mirrors the federal one, and the same distribution-first habit applies. Fund it through a distribution to yourself, then pay from your personal account.
State rules vary quite a bit. Some states have no individual income tax at all. Washington is one example, though note it still has other business taxes that can affect your practice even without a personal income tax. Other states require estimated payments only when your expected balance due passes a certain threshold. If your state does not require a quarterly payment, you are still not off the hook for saving. Keep setting that state portion aside in your tax account and hold it there until you file. When the bill comes due, the money is already waiting.
Now the PTET exception. If you have made a pass-through entity tax election, which lets the business pay state tax on your behalf, that payment is meant to come from the business account rather than your personal one. PTET does not apply to every entity type or every owner, and its payment deadlines can differ from your personal estimated tax dates, so do not assume it follows the June 15 schedule. The mechanics and timing also affect your federal deduction, so work directly with your CPA on how and when to make those.
The deduction cap for state and local taxes rose to about $40,400 for 2026 under the new law, though it phases down for higher earners and reverts to $10,000 in 2030. Even with that higher cap, a PTET election still carries real value for many owners. Worth confirming with your CPA based on your income.
Pay the federal and state portions separately. They go to different places.
One last caveat. In years when the IRS grants disaster relief for a federally declared disaster, estimated tax deadlines can be pushed back for taxpayers in the affected areas. If a major storm, wildfire, or similar event hits your region near a due date, check whether relief applies before assuming the standard date.
The Bottom Line
Estimated taxes feel intimidating, but the system that keeps you safe is genuinely simple.
Move a percentage of every profit dollar into a dedicated tax savings account as you earn it. Use 25 percent federal as your baseline if you are an owner, 30 percent if you are a 1099 doctor, and scale up as your income grows. Add your state on top. Then make your payment by June 15 and keep going.
The set-aside keeps you safe. The quarterly check-in with your CPA keeps you accurate.
Do not let this one sneak up. Mark June 15 today, and you will sail through it.
A Note for Our Clients
If you are a Refractional CFO client, we have already done the heavy lifting for you. We calculate your quarterly estimates and upload them to your client portal before the due date, so you are not left guessing at the numbers.
Before June 15, log into your portal and check for your Q2 estimates. If they are there, you are all set. Just follow the payment steps above.
If you do not see them, reach out directly to your Client Success Manager and we will get you a copy right away. We would always rather hear from you a few days early than have you miss the deadline.
