If you file Texas sales and use tax quarterly, October 20, 2026 is the due date to report July through September. Monthly filers also hit the 20th for the September period. The Texas Comptroller publishes those windows plainly on the Sales and Use Tax pages and the File and Pay calendar.
The filing gets quieter when the books already know the story for that window. Taxable versus nontaxable coding, local rate detail that matches where you sold, and a closed July to September picture beat rebuilding July from memory in filing week. Think books literacy for the report window, not legal advice on whether a specific item is taxable.
What the Comptroller calendar is asking for
Quarterly filers report January through March by April 20, April through June by July 20, July through September by October 20, and October through December by January 20. Monthly filers report on the 20th of the month following the reporting month. If a due date falls on a weekend or legal holiday, the next working day applies. For October 20, 2026, a Tuesday, the ordinary due date stands.
Returns filed through Webfile must be submitted by 11:59 p.m. Central Time on the due date. The Comptroller notes late filing and late payment penalties for returns and tax that miss the window, including a late filing penalty and percentage penalties that step up when tax stays unpaid. The soft teaching point for owners is upstream of those penalties: do not invent the July to September story under a clock. Build it while the months are still close enough to remember.
What the books need before you file
Taxable sales coded cleanly. Exempt or nontaxable activity not mixed into the taxable bucket. Local rate detail that matches the address or jurisdiction story for the sale. A reconciled window so cash, invoices, and the report are not three different novels fighting each other on the same desk.
When everything sat in one “sales” line all summer, Oct 20 becomes a scavenger hunt. Hill Country shops that sell across Boerne, Kerrville, Fredericksburg, Comfort, and beyond feel that pain faster because local rates and special purpose districts vary by place. The Comptroller’s Sales Tax Rate Locator exists for a reason. Your books still need to keep up with where the sale happened, not only that a sale happened.
An illustrative quarter tie out
Here is a hypothetical example with round numbers. It is for teaching only, does not describe a real business, and is not a statement about how any particular item is taxed.
Say a small retail shop in Fredericksburg records $90,000 in total sales for July through September. The books show $70,000 coded as taxable and $20,000 coded as nontaxable, such as sales supported by exemption or resale documentation. At a combined local rate of 8.25 percent, tax on the taxable sales works out to $5,775.
Before filing, the owner checks three places. The sales report says taxable sales were $70,000. The sales tax payable account in the books shows $5,600 collected, not $5,775. And bank deposits for the quarter run about $500 higher than the sales report.
None of those gaps is a disaster. Each one is a question. The $175 difference in tax might be a few invoices coded nontaxable by mistake, a refund that reversed tax, or a discount applied after tax. The deposit gap might be a customer paying an old invoice from June, or a transfer that landed in the wrong account. Finding those answers in early October takes an afternoon. Finding them at 10 p.m. on October 20 takes a lot more than an afternoon, and usually some guessing.
The point of the example is the habit, not the numbers: the sales report, the tax liability account, and the bank should tell one story before the return asks for totals.
Why local rates deserve a second look in the Hill Country
Texas pairs a state sales tax rate with local taxes that cities, counties, transit authorities, and special purpose districts may add. The combined rate a customer pays in one town may not match the next town down the road. A shop based in Boerne that delivers to Comfort, sells at a weekend market in Kerrville, and ships an order to San Antonio can touch several local rate situations in one quarter.
The Comptroller’s Sales Tax Rate Locator lets you look up rates by address. The books side of the job is making sure each sale carries a location and a tax code that match what actually happened, so the return can be built from records instead of memory. Where a sale is sourced for local tax is a question for your tax pro. Keeping clean location detail in the books is how you make that conversation short.
A pre filing checklist
- Close July, August, and September in the books and reconcile the bank for each month.
- Run a sales report for the window split by taxable and nontaxable.
- Spot check a handful of invoices against their tax codes.
- Compare tax collected in the books to the sales tax payable balance.
- Confirm each selling location has the right local rate, using the Comptroller’s rate locator.
- Collect exemption and resale documentation for nontaxable sales in one folder.
- List open questions for your tax pro in one place.
What to do this week
Close the July to September coding now. Spot check a handful of invoices against taxable versus nontaxable tags. List open questions for your tax pro in one place instead of in message threads you will not find in filing week. File from a report you trust, not from a reconstructed guess.
If you are monthly, treat the September close with the same seriousness. If you are quarterly, treat the full three month window as one story you can defend. Our part is keeping the books ready for that window. Return positions, exemption questions, and edge case commodity calls stay with your tax professional. Clean coding makes their job quieter and yours shorter.
One more Hill Country note: if you collect in multiple cities or special purpose districts, do not wait until filing week to notice a rate change or a new location that never got a clean tax code in the books. October 20 rewards shops that treated July, August, and September as reportable months while they were still open, not as a puzzle to solve later.
And if you opened a second location, started selling at markets in San Antonio, or added delivery since spring, give those sales a close look first. New ways of selling are where coding most often drifts.
Before you file
Not tax advice. Books literacy only. Match the books to the Oct 20 window.
Sources
Texas Comptroller: Sales and Use Tax (quarterly due dates including Oct 20 for July to September): https://comptroller.texas.gov/taxes/sales/
Texas Comptroller: File and Pay: https://comptroller.texas.gov/taxes/file-pay/
Texas Comptroller: Due dates for taxes, fees and information reports: https://comptroller.texas.gov/taxes/file-pay/due-dates.php
Texas Comptroller: Sales Tax Rate Locator (local rates by address): https://gis.cpa.texas.gov/search/
