Colorado Sales Tax Filing for Small Businesses

Colorado sales tax is rarely one return. A business may owe the state, plus one or more home-rule cities that run their own sales tax. SB Tax & Accounting, based in Aurora, provides sales tax preparation and filing for businesses in Aurora, Denver, Parker and Centennial, so every return is filed in the right place and on time.

How Colorado decides when you file

The Department of Revenue sets your filing frequency from the amount of sales tax you collect each month (Colorado DOR). A monthly return is due on the 20th of the following month, and a due date that falls on a weekend or holiday moves to the next business day. You must file every period, even when you made no sales and collected no tax.

Starting January 1, 2026, new Department of Revenue rules require sales tax returns to be filed electronically, on a schedule based on prior-year sales (Colorado DOR e-filing rules).

State returns and home-rule city returns

Some Colorado cities are home-rule, self-collecting jurisdictions with their own sales tax. The state's Sales & Use Tax System lets you file state returns and returns for participating home-rule cities in one place (SUTS). Participation is voluntary for those cities, and their taxes can be filed through SUTS or directly with the city (SUTS FAQ). The current list of participating cities is kept by the state (participating jurisdictions).

In practice, that means a store with locations in more than one city can owe returns in more than one system. Filing the state return alone does not cover a self-collecting city.

What our sales tax service covers

• State of Colorado sales tax returns
• Home-rule city returns for Denver, Aurora and other self-collecting cities
• Sales tax license setup and renewals for new locations
• Reconciling your POS sales reports to what gets filed, so the numbers match
• Back filings and penalty resolution if you have fallen behind

Sales tax return preparation starts from your own sales data. We reconcile the POS reports each period, which is also what makes the returns easy to support later. See the full sales tax service page for details.

How we work together

It starts with a free 45-minute strategy call to review your returns, books and filing calendar. Next we bring the books current and set every recurring deadline. After that, returns are filed and monitored on schedule all year. Clean monthly bookkeeping keeps each sales tax return quick to prepare, and grocery and other retail owners can read how that works in bookkeeping for grocery stores.

Our office is in Aurora at 2851 S Parker Rd, Suite 912, and we speak English, Nepali and Spanish.

This page is general information, not tax or legal advice. Rules change, so check the linked Colorado Department of Revenue and IRS pages or talk to a tax professional before acting.