Connecticut Small Business Due Dates
I use my calendar to keep track of forms and payment due dates for Connecticut, including town, state, and federal requirements. Some dates and requirements vary based on the specific business structure (e.g., sole proprietorship, LLC, or corporation) and industry. Check with your CPA and town’s website for local filings and taxes. This calendar is just a general list and is not all-inclusive for every business.
Monthly
1. Sales and Use Tax Return
Due Date: 20th of each month (if required to file monthly)
Responsible Agency: Connecticut Department of Revenue Services (DRS)
Action: File Form OS-114 (Sales and Use Tax Return) if your business collects sales tax.
Resource: Connecticut DRS Sales and Use Tax
Payment: Online via myconneCT
2. Payroll and Employment Taxes (for Employers)
Due Date: 15th of each month (federal), Connecticut varies by payroll frequency
Responsible Agencies: IRS and Connecticut DRS
Action: File Form 941 (Quarterly) or make monthly deposits for employment taxes (federal). State withholding tax may also be due.
Resources:
IRS Payroll Tax Info
CT Employer Withholding Tax Info
Payment:
Quarterly
1. Federal Estimated Tax Payments (for Sole Proprietors, LLCs, etc.)
Due Dates: April 15, June 15, September 15, January 15 (of the next year)
Responsible Agency: IRS
Action: Pay estimated taxes using Form 1040-ES
Resource: IRS Form 1040-ES
Payment: Online via IRS Direct Pay
2. Connecticut Estimated Business Income Tax Payments
Due Dates: April 15, June 15, September 15, January 15 (of the next year)
Responsible Agency: Connecticut DRS
Action: File Form CT-1040ES
Resource: CT Estimated Tax Info
Payment: Online via myconneCT
3. Federal Payroll Tax Return (Form 941)
Due Dates: April 30, July 31, October 31, January 31 (if monthly payments aren’t made)
Responsible Agency: IRS
Action: File Form 941 (Employer’s Quarterly Federal Tax Return)
Resource: IRS Form 941
Payment: IRS EFTPS
4. Connecticut Unemployment Quarterly Reports (for Employers)
Due Dates: Last day of the month following the end of the quarter (April 30, July 31, October 31, January 31)
Responsible Agency: Connecticut Department of Labor
Action: File UC-2 and UC-5A for unemployment tax reporting.
Resource: CT Department of Labor UC Reports
Payment: Online via CT DOL Employer Services
Annually
1. Federal Income Tax Return (Form 1040 for Sole Proprietors or LLCs)
Due Date: April 15
Responsible Agency: IRS
Action: File personal/business income tax return. Include Schedule C for business income if applicable.
Resource: IRS Form 1040
Payment: IRS Direct Pay
2. Connecticut Income Tax Return (Form CT-1040 for Sole Proprietors or LLCs)
Due Date: April 15
Responsible Agency: Connecticut DRS
Action: File state income tax return. Include Schedule CT-1040C if necessary.
Resource: CT-1040 Form
Payment: myconneCT
3. Connecticut Annual Business Report (for LLCs and Corporations)
Due Date: Annually, due date based on your LLC’s registration date (Check the Secretary of State’s website)
Responsible Agency: Connecticut Secretary of State
Action: File your LLC or Corporation’s annual report.
Resource: CT Secretary of State Annual Filing
Payment: CONCORD Filing System
4. Personal Property Tax Declaration (for businesses with tangible personal property)
Due Date: November 1
Responsible Agency: Local town or city tax assessor's office
Action: File personal property tax declaration with your town.
Resource: Contact your local town hall or CT Town Websites
5. Business License Renewals (if applicable)
Due Date: Varies by town and license type
Responsible Agency: Local municipality or relevant Connecticut regulatory authority
Action: Renew business-specific licenses
Resource: Check with your local town hall or CT Business Licenses
Town-Specific Deadlines
Contact your town's tax office or small business department for local filings. Local business registration and license renewal due dates can vary.:
Town Clerk’s Office: Responsible for business registrations and trade name certificates.
Local Tax Assessor: Responsible for personal property taxes and business equipment declarations.
Most of my business clients are in New Milford and Washington, so here’s my list for those towns (other local towns have similar requirements and due dates):
New Milford, CT
1. Personal Property Tax Declaration
Due Date: November 1 (annually)
Responsible Agency: New Milford Assessor's Office
Action: All businesses that own tangible personal property (e.g., machinery, furniture, computers) must file a Personal Property Declaration by this date.
Penalty: Failure to file results in a 25% penalty.
2. Real Estate Taxes (if business owns property)
Due Dates: July 1 and January 1 (semi-annual installments)
Responsible Agency: New Milford Tax Collector
Action: Pay real estate taxes in two installments.
Tax Payment Portals
You can pay property and real estate taxes online:
3. Business License Renewal (if applicable)
Due Date: Varies based on license type (annual renewal)
Responsible Agency: New Milford Town Clerk’s Office or applicable regulatory body
Action: Renew any business licenses or permits required for your business operations (e.g., food service, liquor license).
4. Trade Name Certificate (DBA)
Due Date: Upon opening the business (no annual filing required)
Responsible Agency: New Milford Town Clerk’s Office
Action: Register your business’s trade name if operating under a name other than your own personal name.
Washington, CT
1. Personal Property Tax Declaration
Due Date: November 1 (annually)
Responsible Agency: Washington Tax Assessor's Office
Action: File a Personal Property Declaration for any business-owned equipment or tangible property.
Penalty: A 25% penalty is assessed for late filings.
2. Real Estate Taxes (if business owns property)
Due Dates: July 1 and January 1 (semi-annual installments)
Responsible Agency: Washington Tax Collector
Action: Pay real estate taxes in two installments for any business-owned property.
3. Business License Renewal (if applicable)
Due Date: Varies depending on license type (annual renewal)
Responsible Agency: Washington Town Clerk’s Office or applicable authority
Action: Renew any licenses specific to your industry (e.g., food service, contractor licenses, etc.).
4. Trade Name Certificate (DBA)
Due Date: Upon business registration (no annual renewal required)
Responsible Agency: Washington Town Clerk’s Office
Action: Register a trade name (DBA) if operating under a name other than your personal name.
Tax Payment Portals
You can pay property and real estate taxes online:
