How to File Connecticut Sales Tax Online

Learn how to file sales tax online in Connecticut with step-by-step instructions including screenshots.

By
Sam Ross
Sam Ross
Co-founder, Numeral

Prior to Numeral, Sam started numerous e-commerce businesses that have generated over $50M in revenue. However, the headache of filing sales taxes across many states became the basis for starting Numeral. Thousands of filings later, Sam's a pro at ecommerce sales tax.

Reviewed by
Nate Matherson
Nate Matherson
Head of Growth

Nate is the Head of Growth at Numeral. He has founded multiple venture-backed companies and is a two-time Y Combinator Alum. He is based in Charleston, SC.

Published:
March 10, 2026
Updated:
March 11, 2026

Step-by-step process for filing sales tax in Connecticut

Let’s get right into the steps to file and pay your Connecticut sales tax returns.

Step 1: Access the Connecticut myconneCT services website

To begin the process of filing and paying your sales tax return, follow this link: https://drs.ct.gov/eservices/_/

This will take you to the Connecticut Department of Revenue Services website, where you'll see a login screen.

Step 2: Sign in to your DOR services account

On the login screen, you'll need to enter your username and password. If you don't have a username and password, you'll need to create those first. There is a $100 registration fee to obtain a sales tax permit.  These login credentials are typically created when you submit registration paperwork for a sales tax permit. 

If you'd rather not handle the process of obtaining a permit or setting up a state login yourself, Numeral’s white-glove sales tax service can take care of that for you.

Step 3: Navigate to the sales and use tax filing page

Once you've successfully logged in, you'll be directed to your dashboard. From there, locate the "Sales and Use Tax" link under the "File a Return" section and click on it.

Step 4: Select the correct filing period and begin preparing your return

On the next page, you'll see a drop-down menu where you can select the appropriate filing period. Choose the correct period and click "Next" to proceed to the page where you'll prepare your return. At this point, you'll see instructions referencing different sales tax rates in Connecticut. 

Step 5: Enter your gross receipts and deductions

Connecticut's sales tax return is relatively straightforward. At this step, you'll need to enter your gross receipts and any applicable deductions. If you have deductions to report, click the blue "deductions" button.

This will take you to a new screen where you can choose the appropriate deduction from the drop-down menu and enter the corresponding amount. 

Once you've entered the deduction, select "Enter deduction," and it will appear on a line directly where you keyed in the amounts. Navigate back to the previous menu, where you should now see both your gross receipts and deductions.

Click "Calculate" to determine the total tax due. If you have any sales that fall under the 7.75% or 9.35% rates, repeat this process for those categories as well.

When you've finished entering all the necessary information, click "Next" at the bottom of the page.

Step 6: Finalize and submit your sales tax return

You'll now be directed to a summary screen where you can review the information you've entered for accuracy. Take a moment to ensure that everything is correct before proceeding.

Step 7: Pay your Connecticut sales tax 

After reviewing your return, you'll be taken to a page where you can submit payment along with your return. Connecticut allows you to submit both your return and payment simultaneously.

Select the payment option that applies to you. For electronic payments, choose the "Direct Payment" option at the top of the page.

Before submitting your payment, double-check that your bank information is correct and that the payment date you've selected is on or before the return's due date to avoid any late fees.

As a general rule, avoid using your browser's back arrow to navigate within any state sales tax portal. Instead, use the navigation buttons provided on the site to move between pages.

Congratulations! You've successfully filed and paid your Connecticut sales tax return.

Local sales tax rates in Connecticut

The Connecticut sales tax rate is 6.35%. This comprises a base rate of 6.35% plus no additional mandatory local rates. Since there are no local taxes, the 6.35% statewide rate applies uniformly across the state.

Filing Sales Tax in Connecticut FAQs

When are Connecticut sales tax returns due? 

Connecticut sales tax returns are generally due on or before the last day of the month following the reporting period. For example, if you're filing a return for the first quarter (January through March), the due date would be April 30th.

What happens if I file my Connecticut sales tax return late?

If you file your sales tax return late, you may be subject to penalties and interest. The penalty for late filing is 10% of the tax due, with a minimum penalty of $50. Interest accrues on the unpaid tax at a rate of 1% per month or a fraction of a month from the due date until the tax is paid in full.

Can I file a Connecticut sales tax return without making a payment? 

Yes, you can file your sales tax return without making a payment. However, keep in mind that if you owe tax and don't pay it by the due date, you'll be subject to penalties and interest as described above.

What if I need to amend a previously filed Connecticut sales tax return? 

If you need to amend a previously filed return, you can do so by logging into your account on the Connecticut Department of Revenue Services website and selecting the period you need to amend. Make the necessary changes and submit the amended return. If the changes result in additional tax due, be sure to include payment to avoid penalties and interest.

Is SaaS taxable in Connecticut?

Yes, SaaS is taxable in Connecticut in most cases. The exact rate depends on your product category.

Simplify your sales tax compliance with Numeral

If you're feeling overwhelmed by the complexity of sales tax compliance for your business, you're not alone. Keeping track of tax laws, registering in multiple states, and filing returns on time can be a daunting task. 

That's where the Numeral comes in.

Numeral is your all-in-one solution for sales tax compliance. We take the stress and hassle out of managing sales tax, so you can focus on what matters most—growing your business. With Numeral, you'll spend less than five minutes a month worrying about sales tax.

Here's what Numeral can do for you:

  • Monitor your sales 24/7 and notify you when you reach economic nexus
  • Register your business in all states where you have nexus
  • Manage your store's tax collection settings to ensure you're collecting the right rates across 11,000 tax jurisdictions
  • Automate monthly, quarterly, and annual remittances on your behalf
  • Integrate seamlessly with your ecommerce or billing platforms
  • Provide 24/7 live chat support and strategic tax advice from licensed CPAs
  • Communicate with state agencies on your behalf and process all your state mail

Don't let sales tax compliance hold you back from reaching your full potential as a business owner. Book a demo with Numeral today and experience the peace of mind that comes with knowing your sales tax is handled by the best in the business. 

About the author

Sam Ross

Prior to Numeral, Sam started numerous e-commerce businesses that have generated over $50M in revenue. However, the headache of filing sales taxes across many states became the basis for starting Numeral. Thousands of filings later, Sam's a pro at ecommerce sales tax.

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