Connecticut Sales Tax Guide for E-commerce Sellers

Rate structure

Connecticut's state rate is 6.35%; the combined state + local rate ranges from 6.35% (flat). Sourcing: Destination.

COMPONENTRATENOTES

State rate6.35%myconneCT general statewide rate

Local taxes6.35% (flat)No local sales tax — one flat 6.35% statewide (7.75% luxury rate on some goods).

ReturnForm OS-114 Sales and Use Tax ReturnForm OS-114 Sales and Use Tax Return (flat 6.35%, Column 1)

Economic nexus threshold

You must register and collect once your Connecticut sales reach $100,000 and 200 orders, measured over the preceding 12 months. Both the sales and the order-count tests must be met. BOTH tests required (12-month period ending Sept 30). Marketplace sales count toward this threshold even though the marketplace collects for you.

Where you stand: SalesTax50 tests your imported sales against this exact rule and flags Connecticut as Approaching or Exceeded on your Nexus page — check my nexus free →

Filing frequency

myconneCT assigns a filing frequency at registration based on expected tax liability and adjusts it over time. Frequencies used in Connecticut: Monthly · Quarterly · Annual.

Due dates

Returns are due on the last day of the month following the period. When the due date falls on a weekend or holiday it moves to the next business day.

Late filing: 15% of tax due or $50, plus 1% interest per month.

Marketplace facilitator rules

Since December 2018, marketplace facilitators (Amazon, eBay, Walmart, TikTok Shop) collect and remit Connecticut tax on your marketplace sales. How Connecticut treats them:

Who collects?Facilitatoron marketplace orders; you collect on Shopify / your own site.

Count toward nexus?Yesmarketplace + direct sales together determine your threshold status.

Do you still file?YesYes — a registered seller still files, even for periods where all sales were through marketplaces (a zero or marketplace-only return).

How reported?DeductionDeducted on Line 15 of OS-114.

Direct salesYou collectShopify, your own site, invoices — you collect and remit on your return.

Marketplace treatment changes state by state and year by year — SalesTax50 separates marketplace and direct sales automatically, but confirm with Connecticut DRS when in doubt.

Filing portal & AutoFile

Connecticut returns are filed through drs.ct.gov/eservices/_. Login verification: May require verification. SalesTax50 AutoFile prepares the Form OS-114 Sales and Use Tax Return from your imported sales — you review and approve every return before it is submitted.

FAQ

Do I need a Connecticut permit if I only sell on Amazon?

If you exceed the $100,000 and 200 orders threshold or have physical presence (including inventory in Connecticut warehouses), yes — you must register even though Amazon collects for you.

What if I sell on Shopify and TikTok Shop?

TikTok Shop collects as a marketplace facilitator; Shopify does not. You collect on Shopify orders and report both streams on your myconneCT return — SalesTax50 separates them automatically.

Does SalesTax50 file Connecticut returns automatically?

Yes — AutoFile prepares your Form OS-114 Sales and Use Tax Return from imported sales; you approve every return before it is submitted, and a $99 one-time state setup configures your existing Connecticut permit.

Why both $100k AND 200 transactions?

Connecticut is one of only two states (with New York) that requires BOTH tests to be met before economic nexus applies.

This guide is general information for e-commerce sellers, not tax advice. Rates, thresholds and due dates change — confirm with Connecticut DRS before relying on them.

Let AutoFile handle your Connecticut returns

Prepared and checked for you — you approve before anything is filed.

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