Connecticut C-Corporation Compliance Guide
Everything you need to legally form and operate a C-Corporation in Connecticut. Filing fees, tax forms, ongoing requirements, and the trade-offs of this structure.
Is a C-Corporation Right for You?
Startups raising VC funding, businesses planning IPO, or those needing multiple share classes / foreign owners.
Double taxation on distributed profits. Most complex structure. Rarely optimal for small businesses.
Tax treatment
Entity-level federal tax (flat 21%). Dividends taxed again to shareholders (double taxation).
| Item | Connecticut Requirement |
|---|---|
| Formal state filing required | Yes — file Articles of Incorporation with the Connecticut Secretary of State. |
| State filing fee | $250 |
| Federal tax form filed | Form 1120 |
| Employer Identification Number (EIN) | Required — apply free at irs.gov (5 minutes online) |
| Registered agent required | Yes — must have a physical Connecticut address available during business hours. |
| Annual/periodic report | annual — fee $80 |
| State income tax | Corporate income tax applies (see Connecticut DOR). |
Filing Sequence in Connecticut
- 1
Choose a business name
Search Connecticut SoS name database. Reserve the name if desired (~$25 fee, optional).
- 2
Get an EIN from the IRS
Free at irs.gov. Takes ~5 minutes online. Required for all business banking, payroll, and tax filings.
- 3
File formation documents ($250)
Submit Articles of Incorporation to Connecticut Secretary of State. Include registered agent info. Processing ~7 business days.
- 4
Register for state taxes
Register for sales tax if selling taxable goods/services in Connecticut. Register with Connecticut Department of Revenue for state income tax withholding if hiring employees.
- 5
Open a business bank account
Separate business finances from personal. Bank will require EIN, formation docs (for entities), and often an operating agreement.
Compare Other Structures in Connecticut
Not legal or tax advice.
State filing requirements change. Verify fees and deadlines with the ConnecticutSecretary of State and Department of Revenue before filing. Structure choice has tax and liability implications — consult a licensed CPA or attorney for your specific situation.