Connecticut Business Entity Tax and Payroll Setup in 2026: What New LLC Owners Should Sequence First

August 19, 2026

You formed your Connecticut LLC. You have a certificate from the Secretary of State. Now what? Two separate government agencies expect something from you, and neither one is the SOS. The Connecticut Department of Labor wants to know about your payroll. The Connecticut Department of Revenue Services wants to know about your Business Entity Tax. These are not the same thing. They have different deadlines, different penalties, and different forms. Getting the sequence wrong — or missing one entirely — is one of the most common and most expensive mistakes new Connecticut LLC owners make in year one.

This guide covers what each obligation is, when it starts, what happens if you miss it, and the correct order to handle everything.

What Is the Connecticut Business Entity Tax

The Connecticut Business Entity Tax is a state entity-level tax on LLCs, partnerships, and S corporations that are treated as pass-through entities for federal tax purposes. If your LLC is a single-member disregarded entity or a partnership for federal tax purposes, the BET may not apply to you directly. But if you elected S corporation or C corporation status for federal tax purposes, or if your multi-member LLC is classified as a partnership, you owe the BET.

The BET rate is 7.5 percent of your net income attributable to Connecticut. There is a $250 minimum tax regardless of whether your business had income. This catches a lot of small LLC owners off guard — even a year where your Connecticut business ran at a loss still triggers a $250 BET minimum payment.

The tax is administered by the Connecticut Department of Revenue Services. The filing deadline is the 15th day of the fourth month after your fiscal year ends. For calendar-year businesses, that is April 15. You file using the OS-ACT form for S corporations or the OP-EST form for partnerships, depending on your election.

If your LLC is a disregarded single-member entity for federal tax purposes — meaning you report LLC income on your personal Schedule C — you do not file a separate Connecticut BET return. Your Personal Income Tax return captures the income. But once you elect S corporation status to reduce self-employment tax, the BET kicks in immediately for that tax year.

What Triggers Connecticut Payroll Obligations

You do not need employees to have a payroll obligation in Connecticut. If you have employees — even one part-time worker — you have a payroll compliance chain that starts before the first paycheck.

The chain includes federal withholding (Social Security, Medicare, federal income tax), Connecticut withholding (state income tax), Connecticut unemployment insurance through the CT Department of Labor, mandatory Connecticut Paid Leave coverage, and workers compensation insurance. Each agency has its own registration, its own filing calendar, and its own penalty schedule.

Even if you are the only person drawing money from the LLC, you may still have a payroll decision to make. Some Connecticut LLC owners elect S corporation status specifically to pay themselves a “reasonable salary” through payroll and reduce self-employment tax. If that is your plan, you need a payroll system set up from day one of the election. The IRS and CT DRS both expect payroll tax filings to match the salary you report as a W-2 employee of your own LLC.

Step 1: Get Your Federal EIN First

Every Connecticut LLC with employees, or that has elected corporate tax status, needs a Federal Employer Identification Number from the IRS. Apply online at irs.gov. The process takes about five minutes during IRS business hours and the number is issued immediately. There is no filing fee.

Keep the EIN confirmation somewhere permanent. You will need it for every subsequent registration in this guide. The CT Department of Labor, the CT DRS, and your payroll processor all start with the EIN.

If your LLC is a single-member disregarded entity with no employees and no plans to elect corporate status, you may be able to use your personal Social Security number for banking and contracts. But even most single-member LLCs eventually get an EIN because banks increasingly require it for business accounts.

Step 2: Register with the Connecticut Department of Labor for Unemployment Insurance

The CT Department of Labor handles unemployment insurance through the Tax and Benefits system. Any Connecticut employer with one or more employees must register for employer coverage, even if the employee works part time.

Connecticut unemployment insurance is experience-rated, which means your tax rate starts at a standard new employer rate and adjusts based on your claims history over time. The new employer rate for most service-sector businesses is approximately 3.0 to 3.5 percent on the first $25,200 in wages per employee (the 2026 Connecticut taxable wage base). Retail and construction employers typically see higher rates.

Register through the CTDOL online employer registration portal. You will need your EIN, your business start date, and your estimated quarterly payroll. The registration is free. Once registered, you will file quarterly wage reports and pay unemployment taxes quarterly.

One important note: Connecticut is one of the more aggressive states when it comes to auditing employer accounts. If your payroll figures look inconsistent quarter to quarter, or if you have independent contractors you later reclassify as employees, the CTDOL may open an audit. Regular, consistent quarterly filings are your best protection.

Step 3: Register with Connecticut DRS for Withholding Tax

The Connecticut Department of Revenue Services administers state income tax withholding for employees. Any Connecticut employer withholding state income tax from employee paychecks must register with DRS through the myconnexus portal.

You will register for the Form CT-941 — Connecticut Withholding Tax return — which is filed quarterly. The filing deadline is the last day of the month following the quarter (April 30, July 31, October 31, and January 31). If your withholding liability exceeds a certain threshold, you may be required to file monthly instead.

The Connecticut withholding rate varies based on the employee’s Form CT-W4 elections and the state tax tables. The tax tables are published by DRS and updated annually. Use the current tables from the DRS website — using outdated tables is a common source of over- or under-withholding errors.

DRS also administers the Connecticut Paid Leave program. Since 2021, Connecticut requires most employers to withhold Paid Leave contributions from employee wages and remit them to DRS. The contribution rate for 2026 is 0.5 percent of covered wages, up to the Social Security wage base. Both the employer contribution and the employee withholding apply, though some employers cover the employee portion. Verify your obligations through DRS before setting up payroll.

Step 4: Set Up Federal Payroll Tax Withholding

Federal payroll tax withholding is independent of your Connecticut state obligations. You withhold Social Security and Medicare from every paycheck under FICA — 6.2 percent for Social Security (on wages up to $168,600 in 2026) and 1.45 percent for Medicare with no wage cap. As the employer, you also pay the matching amounts.

Federal income tax withholding uses the employee’s Form W-4 elections and the IRS Publication 15-T withholding tables for the current year. The IRS updates the tables each year and sometimes mid-year when legislation changes. Always confirm you are using the current year’s tables.

You will file Form 941 — the Employer’s Quarterly Federal Tax Return — with the IRS. The filing deadline is the last day of the month following each quarter. Penalties for late filing or missed deposits are substantial and accumulate quickly.

Most small Connecticut LLCs use a payroll service to handle federal and state withholdings automatically. The monthly subscription cost — typically $25 to $60 — is less than the cost of a single missed Form 941 penalty or a CT-941 late filing penalty.

Step 5: Arrange Workers Compensation Insurance

Connecticut requires virtually all private employers to carry workers compensation insurance. This is a commercial insurance policy that covers medical costs and disability payments for employees injured on the job. It is not optional.

There are very narrow exceptions — certain agricultural employers, employers with fewer than three employees in specific classifications, and sole proprietors with no employees may be exempt. But every Connecticut LLC with even one W-2 employee should carry workers comp unless a licensed insurance professional confirms a specific exemption applies.

Workers comp premiums are based on your payroll, the classification codes for your employees’ work, and your claims history. Office-only businesses with clerical staff typically pay $400 to $800 per year. Construction, manufacturing, and service businesses with physical labor pay substantially more.

Get at least two quotes from carriers authorized in Connecticut. Do not operate without this coverage. An uninsured Connecticut employer who faces a workplace injury claim can lose personal assets in a lawsuit.

Step 6: File Your First Connecticut Business Entity Tax Return

If your LLC is classified as an S corporation or partnership for federal tax purposes and you have Connecticut-source income, you must file the appropriate Connecticut Business Entity Tax return. For S corporations, this is the OS-ACT form. For partnerships, it is the OP-EST form.

The return is due by the 15th day of the fourth month after your fiscal year closes. For a calendar-year business, that is April 15. You can request an automatic six-month extension using Form CT-1127, but the extension applies only to the filing deadline — not to any tax payment due.

The BET is calculated on net income from Connecticut sources. If your Connecticut operations generated $100,000 in net income and you are an S corporation, the BET would be $7,500 on that income. The $250 minimum applies if your net income calculation results in a lower tax amount.

If your LLC is a disregarded single-member entity, you do not file a separate BET return. Your Connecticut Personal Income Tax return (Form CT-1040 or CT-1040ES) captures the LLC income through the passthrough. The distinction matters because the filing procedures and deadlines are different.

Why Sequence Matters

The order of these steps is not arbitrary. You need an EIN before you can register with the CTDOL or DRS. You need your CTDOL account number before you can file your first quarterly wage report. You need a workers comp policy number before you finalize certain contracts or leases. Each step unlocks the next.

Most new Connecticut LLC owners who run into trouble do so because they treated payroll and tax compliance as a single task rather than a sequence. They set up a payroll service but forgot to register with the CTDOL for unemployment insurance — which means they were technically out of compliance from their first payroll onward. The CTDOL can back-assess unemployment taxes going back four years with interest and penalties.

A reliable sequence is: EIN first, CTDOL registration second, DRS withholding registration third, workers comp fourth, payroll service or accountant fifth. If you are also electing S corporation status, that decision should precede setting up payroll so your payroll system correctly handles W-2 wages vs. distributions.

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