Self-employed in Southeast LA? Prepare now for the September 2026 estimated-tax deadline
Organize income, expenses, prior payments, and your 2026 estimate before the September 15 payment date so you can calculate and document the next step.
Key takeaways
The IRS lists September 15, 2026 as the third estimated-tax payment date for calendar-year individuals.
Estimated payments can cover both income tax and self-employment tax when withholding is not enough.
Recalculate when income changes and keep confirmation of every payment instead of relying on a rough quarterly guess.
Know which 2026 payment is next
For calendar-year taxpayers, IRS Publication 505 lists the 2026 estimated-tax dates as April 15, June 15, September 15, and January 15, 2027. The September payment generally covers the June 1 through August 31 payment period.
A due date is not a reason to send the same amount automatically. If work slowed down, increased, or started during the year, use the current 2026 worksheet or ask a preparer whether the annualized-income method may apply.
Build the estimate from current records
Start with year-to-date business income, ordinary expense records, prior estimated payments, and any tax already withheld from another job. Publication 505 explains that federal tax is pay-as-you-go and that self-employed people generally use estimated payments when withholding does not cover the tax.
Separate business and personal spending, reconcile payment apps and bank deposits, and total mileage or other records while they are still fresh. The goal is a supportable estimate, not a perfect shoebox of receipts on the due date.
- Year-to-date invoices, deposits, and payment-app reports.
- Categorized expense receipts and mileage records.
- Prior 2026 estimated-payment confirmations and any W-2 withholding.
- Your 2025 return and the current 2026 Form 1040-ES worksheet.
Pay under the correct tax year and save proof
Form 1040-ES is used to figure and pay individual estimated tax. When paying electronically, confirm that the payment type and tax year are correct; when using a preparer, ask what amount was calculated and why.
Save the confirmation with your 2026 tax folder. If the amount is late, missing, or uncertain, address it promptly rather than waiting for filing season, because the IRS says an underpayment penalty can apply even when a refund is due later.
Common questions
When is the third 2026 estimated-tax payment due?
For calendar-year individuals, the IRS lists September 15, 2026. Weekend and legal-holiday rules can move a due date in other years, so confirm the current calendar.
Do estimated payments include self-employment tax?
They can. IRS Publication 505 explains that estimated tax is used for income tax and other taxes, including self-employment tax.
