Financial Monday

Arc 5 • Year-End Planning Starts Now • Week 2 of 2

Due Tomorrow:
A Walkthrough

The third-quarter estimated payment is due Tuesday, September 15, federally and in Virginia. Here is what to send and how.

September 14, 2026 12 min read Ladysmith, VA — views

Arc 5 – Year-End Planning Starts Now • Week 2 • Sep 14–18, 2026 Year-End Planning • Q3 2026

MON Sep 14 — You are hereDue Tomorrow WED Sep 16Year-End Tax Moves FRI Sep 18Digital Friday

Arc 5 has spent two posts arguing that the useful work happens early. Today is the exception that proves it: a deadline lands tomorrow, and this is the practical walkthrough.

Then, because the same question always follows, the rest of the calendar. Every date between now and next spring, including two that shift because they fall on weekends.

What Is Due, and Who Owes It

Tuesday, September 15

third-quarter estimated payment, covering income earned June 1 through August 31, due federally and to Virginia on the same date

IRS estimated payment schedule and Virginia Form 760ES

The threshold question is simpler than it sounds. The IRS frames it in terms of the penalty: most taxpayers avoid the underpayment penalty if they owe less than $1,000 in tax after subtracting withholding and refundable credits, or if they paid withholding and estimated tax of at least 90% of the tax for the current year or 100% of the tax shown on the prior year's return, whichever is smaller. Higher-income taxpayers have a separate rule, raising the prior-year figure to 110% where prior-year adjusted gross income exceeded $150,000, or $75,000 if married filing separately.

For most small business owners that means: if you expect to owe $1,000 or more after withholding, this is your deadline. Wednesday's post covers the year-end moves that follow; today is about getting the payment right.

Deciding the Amount

Last Wednesday made the case for choosing a target rather than repeating last quarter. The short version, if you are reading this the day before: the prior-year safe harbor is the practical one because it is a number that already exists. Your return is filed, the figure is fixed, and no forecasting is required.

This year running lower

Consider the current-year test

Target 90% of what you will actually owe
Avoids prepaying against an inflated prior year
Requires a defensible full-year estimate
Keeps working capital in the business

This year running higher

The prior-year number caps you

100% of last year, or 110% above the AGI threshold
Known figure, no estimation risk
Protects from penalty however the year finishes
Set aside the difference for April separately

Meeting a safe harbor prevents the penalty. It does not mean nothing is owed. If this year is genuinely bigger than last, paying 100% of the prior year keeps you penalty-free and still leaves a balance due in April. That balance is real, it arrives at once, and it is the reason to reserve as profit is earned rather than as payments come due.

Free Tool

Estimated Tax Safe Harbor Calculator

Enter last year's tax and AGI and it returns the annual target, the applicable percentage, and what each remaining installment needs to be. Built for exactly this: working out tonight what to send tomorrow.

Open the Tool

Sending It

Two payments, two systems. Neither takes long, and both are easier than the paper alternative if you have not set them up before.

Federal

IRS

IRS Direct Pay, straight from a bank account
Your IRS online account
EFTPS, which requires prior enrollment
Debit or credit card, with a processing fee
Or mail a check with the Form 1040-ES voucher

Virginia

Virginia Tax

Your individual online account at tax.virginia.gov
eForms, no login required
Direct debit from a bank account
Card payment, with a fee
Or mail with the Form 760ES voucher

Two things worth checking before you submit.

First, the tax year and period the payment is applied to. A payment tagged to the wrong year is a genuinely tedious thing to unwind, and the dropdown is easy to skim past. Second, if you are enrolling in EFTPS today for the first time, note that enrollment is not instant, so it is not the right choice for a payment due tomorrow. Direct Pay is.

Save the confirmation number somewhere you will find it in April. Reconstructing which payments were made and when is a routine annoyance at filing time and a completely avoidable one. A note in your bookkeeping file with the date, amount, and confirmation takes fifteen seconds.

“Paying something is materially better than paying nothing, and paying late is better than not paying. The penalty is computed on what is unpaid and for how long.”
Why a partial payment tomorrow still beats waiting until you can pay in full

If the Money Is Not There

This happens, and the instinct to wait until the full amount is available is the wrong one. The underpayment charge accrues on the shortfall for the time it remains outstanding, so a partial payment reduces both the base and the duration.

For context on the cost: the IRS announced that interest rates remain the same for the quarter beginning October 1, 2026, with the rate for individual overpayments and underpayments at 7% per year, compounded daily.

Best Pay the full safe harbor amount tomorrow. Penalty exposure for the period closes entirely, and the question moves to April where it belongs.
Still good Pay what you can tomorrow, the rest as soon as possible. Reduces the amount the charge is computed on and shortens the window it runs for. There is no all-or-nothing rule here.
Worth knowing If you have wage income, withholding is treated differently. As covered last Wednesday, withholding is generally treated as paid evenly across the year for estimated tax purposes regardless of when it was withheld. That route takes payroll lead time, so it is a Q4 plan rather than a tomorrow fix.
Avoid Skipping entirely and intending to catch up in January. The penalty is computed period by period, so a January payment does not repair a September shortfall. It closes the January period, not this one.

New This Year, With an Important Limit

The IRS announced a change to penalty relief on July 8, 2026 that is worth knowing about, along with the reason it probably does not help here.

Automatic Exemption from Penalty, as announced

It replaces First Time Abate: The new Automatic Exemption from Penalty, or AEP, replaces the long-standing First Time Abate administrative relief and is designed to eliminate the need to contact the IRS to request relief for those with a timely compliance history.
Relief is applied without asking: Eligible taxpayers do not need to take action to receive it. Where the IRS applies AEP, the taxpayer receives a notice that relief was granted.
Who qualifies: Taxpayers with a history of filing on time and paying any tax due in the previous three years, or twelve consecutive quarters for quarterly returns. It applies to eligible original returns beginning with tax year 2025 and 2026 quarterly returns.
The transition is under way: During the changeover some qualifying taxpayers may still receive penalty notices and may contact the IRS to request First Time Abate. For original returns with due dates on or after January 1, 2027, FTA is replaced by AEP.

Here is the limit that matters for today.

AEP covers failure-to-file, failure-to-pay, and failure-to-deposit penalties. The estimated tax underpayment charge is a different creature and is not part of what this program suppresses. So a clean compliance history is genuinely valuable, and it is not a reason to treat tomorrow as optional. Taxpayers who do not qualify for AEP may still request relief based on reasonable cause.

Every Date From Here to Spring

Two of these move because the statutory date falls on a weekend. The IRS applies the ordinary rule that a due date landing on a Saturday, Sunday, or legal holiday shifts to the next business day, and Virginia applies the same convention.

Federal and Virginia dates, individuals and small businesses

Q3 estimated payment, federal and VirginiaTue Sep 15, 2026

Extended returns for partnerships and S corporationsTue Sep 15, 2026

Extended individual returnsThu Oct 15, 2026

Last day to place property in service for 2026Thu Dec 31, 2026

Q4 estimated payment, federal and VirginiaFri Jan 15, 2027

W-2 and 1099-NEC to recipients and the governmentMon Feb 1, 2027

Partnership and S corporation returnsMon Mar 15, 2027

Individual and C corporation returns, federalThu Apr 15, 2027

Virginia individual returnsMon May 3, 2027

The two shifted dates: the January 31 information-return deadline falls on a Sunday in 2027 and moves to Monday, February 1; and Virginia's May 1 individual filing date falls on a Saturday and moves to Monday, May 3. Your own dates can differ with a fiscal year, an extension, or an entity type not listed here, so confirm yours rather than adopting this table wholesale.

Put the whole list in your calendar today, with reminders a week ahead. Not the day of. A week of notice is the difference between making a considered payment and scrambling, and it is the only part of this post that takes effect immediately and costs nothing.

EveryCentCounts Advisory — Tax Planning & Bookkeeping

Deadline days should be uneventful.

When the September payment requires an evening of reconstruction, the problem is not the deadline. It is that the books were not current enough to answer a simple question quickly. EveryCentCounts keeps Virginia small businesses in a position where each installment is already known before the date arrives, tracks which federal and Virginia dates actually apply to your entity, and does the year-end work in the months when it still changes something. Book a consultation and let the January payment be the boring one.

A necessary note. This article is general educational information, not tax, legal, or financial advice, and EveryCentCounts is not acting as your advisor through this post. The dates listed are common federal and Virginia deadlines for individuals and small businesses and are not exhaustive; your obligations depend on your entity type, fiscal year, filing history, and circumstances, and disaster relief or other postponements may apply in particular localities. Safe harbor rules, penalty relief programs, and interest rates all have conditions and exceptions beyond what a blog post covers. Confirm your own dates and amounts with IRS guidance and Virginia Tax, and consult a qualified professional about your situation.

Wednesday Closes Arc 5

Wednesday, September 16, takes up the year-end tax moves that genuinely belong in September rather than December, which is where this arc has been heading since it opened. With the deadline behind you and a full-year picture in hand, the remaining decisions are about what you do with the fourth quarter rather than what you owe for the third.

EveryCentCounts

Financial Services & Digital Presence Management — Ladysmith, VA

EveryCentCounts provides accounting, bookkeeping, and CFO advisory services to Virginia small businesses and nonprofits. Arc 5 — Year-End Planning Starts Now — concludes Wednesday, September 16.

References

Internal Revenue Service. “Underpayment of Estimated Tax by Individuals Penalty.” irs.gov. Source for the four estimated payment periods, including September 15 for income earned June 1 through August 31 and January 15 of the following year for income earned September 1 through December 31.
Internal Revenue Service. “Topic no. 306, Penalty for underpayment of estimated tax.” irs.gov. Source for the statement that most taxpayers avoid the penalty if they owe less than $1,000 after subtracting withholding and refundable credits, or paid withholding and estimated tax of at least 90% of the tax for the current year or 100% of the tax shown on the prior year's return, whichever is smaller, and for the note that special rules apply to certain higher income taxpayers.
Internal Revenue Service. “Publication 505, Tax Withholding and Estimated Tax.” irs.gov. Source for the 110% prior-year figure where prior-year adjusted gross income exceeded $150,000, or $75,000 for married filing separately, and for withholding generally being treated as paid evenly throughout the year for estimated tax purposes unless an election is made on Form 2210.
Internal Revenue Service. 2026. “Interest rates remain the same for the fourth quarter of 2026.” News release, August 21, 2026 (Revenue Ruling 2026-15). irs.gov. Source for the rate for individual overpayments and underpayments remaining at 7% per year, compounded daily, for the calendar quarter beginning October 1, 2026.
Internal Revenue Service. 2026. “Eligible taxpayers may receive automatic penalty relief.” irs.gov. Source for AEP replacing First Time Abate; for its application to eligible original returns beginning with tax year 2025 and 2026 quarterly returns and future tax periods; for the qualifying history of filing on time and paying any tax due in the previous three years or twelve consecutive quarters; for eligible taxpayers not needing to take action and receiving a notice when relief is granted; for the transition period during which qualifying taxpayers may still receive notices and may request First Time Abate; for AEP replacing FTA for eligible returns with original due dates on or after January 1, 2027; and for reasonable cause relief remaining available to those who do not qualify.
Internal Revenue Service. 2026. “IRS simplifies penalty relief, introduces automatic process for eligible taxpayers.” News release, July 8, 2026. irs.gov. Source for the announcement date and for AEP being a systemic administrative relief program designed to simplify the process for those with a timely compliance history.
Internal Revenue Service. 2026. “When are quarterly estimated tax payments due?” Frequently asked questions. irs.gov. Source for the rule shifting a due date that falls on a Saturday, Sunday, or legal holiday to the next business day.
Virginia Department of Taxation. 2026. “Individual Estimated Tax Payments” and “Form 760ES.” tax.virginia.gov. Source for the Virginia installment schedule, the September 15, 2026 third installment, and the Virginia individual filing date of May 1.

Let January Be the Boring One

A deadline should not require an evening of reconstruction. EveryCentCounts keeps Virginia small businesses in a position where the number is already known before the date arrives.

Book a Free Consultation