Key figures
Connecticut advisory
2026, with sources
R&D credits that can become cash
Connecticut has two research credits: a non-incremental research and development expenses credit and an incremental research and experimental expenditures credit. What sets the state apart is the exchange. A qualified small business, one with prior-year gross income of $70 million or less, that cannot use its credits because it has no tax can exchange them with the state for 65% of their value. From 2025, qualifying biotechnology companies can exchange at 90%.
For a seed-stage company with $1 million of Connecticut research spending and no taxable income, that turns a credit that would sit on a carryforward schedule for years into a refund within the year. The exchange is claimed on the corporation tax return, so it rewards companies whose books separate qualifying research costs by state.
Angel investors and other 2026 changes
Connecticut Innovations runs the Angel Investor Tax Credit: a 25% credit against an investor’s Connecticut income tax for investments of at least $25,000 in a qualifying Connecticut business. The 2026 legislation dropped the old requirement that the business have fewer than 25 employees with 75% living in Connecticut; from July 1, 2026, at least 50% of its employees must reside in the state. Reservations open and close by fiscal year, so check availability before a round closes.
The same legislation created a credit for qualified small businesses (fewer than 50 Connecticut employees) that offer an individual coverage health reimbursement arrangement, and extended NOL carryforwards to 30 years for losses from 2025 on.
Where founders go wrong in Connecticut
Remote hiring has an outsized effect here. One employee in Stamford creates sales tax and payroll obligations, CT Paid Leave contributions from the first paycheck, and, with paid sick leave reaching employers with one or more employees in January 2027, a leave policy too.
- Assuming the 10% surtax is only for $100 million companies; combined groups pay it too.
- Forgetting the 50% NOL cap when forecasting the first profitable year.
- Charging 6.35% on SaaS sold to businesses instead of the 1% rate, or charging nothing.
- Paying semi-monthly without approval: Connecticut’s default is weekly pay.
- Missing the January 31 state 1099 filing because the IRS filing was done.
The federal baseline
This page covers what Connecticut adds. The federal rules underneath it apply here too.
Common questions
Can a loss-making startup turn Connecticut R&D credits into cash?
Yes, if it qualifies as a small business. A company with prior-year gross income of $70 million or less that cannot use its research and development credits can exchange them with the state for 65% of their value, as a refund. Qualifying biotechnology companies can exchange at 90% from 2025.
Is there an incentive for our angel investors?
Through the Angel Investor Tax Credit, administered by Connecticut Innovations. Investors who put at least $25,000 into a qualifying Connecticut business get a credit of 25% against their Connecticut income tax. For taxable years from July 1, 2026, the business must have at least 50% of its employees residing in Connecticut.
Advisory next door
- MAMassachusetts advisoryMassachusetts offers a research credit with a long carryover, a 4% surtax on income over $1,107,750 that a share sale can trigger, and a strict ABC test for contractors.
- NYNew York advisoryNew York’s incentives are refundable but by application, through Empire State Development. The 2026 budget kept the 7.25% cliff rate, decoupled from R&E expensing, and left QSBS alone.
- RIRhode Island advisoryRhode Island’s research credit runs 22.5% then 16.9%, now with a 15-year carryover, but NOLs expire after five years. The two clocks are what to model.
Founder guides on this
- R&D taxThe R&D tax credit and Section 174A for startupsEngineering salaries can earn a federal R&D credit against payroll tax, and Section 174A lets you deduct US research again. What qualifies, what to track.
- SAFEsHow to account for SAFEs on your balance sheetA SAFE is cash today and shares later. Why it usually sits with liabilities, how the cap and discount set conversion, and what to book at the priced round.
- ComplianceFirst-year compliance calendar for a Delaware C-corpDelaware franchise tax, 1099s, the federal return, payroll filings, state annual reports and sales tax: the deadlines a young C-corp misses most, by month.
- RunwayBurn rate and runway: how to calculate them correctlyGross burn, net burn and months of runway, done the way an investor checks them: from cash, averaged, and with the hires you’ve already committed to.
More of the Connecticut guide
- AccountingAccounting and state tax in ConnecticutCorporate tax, conformity to federal rules, apportionment and what it does to your books
- ReceivablesReceivables and sales tax in ConnecticutSales tax registration, economic nexus, whether SaaS is taxable, and collecting from customers
- PayablesPayables and contractors in ConnecticutPaying vendors and contractors: 1099 filing, use tax, contractor tests and withholding
- PayrollPayroll taxes and employer rules in ConnecticutWithholding, unemployment insurance, paid leave, minimum wage and the rules on paydays
- ComplianceCompliance and filings in ConnecticutRegistering to do business, annual reports, franchise tax and the filing calendar
Sources
Checked against each agency’s own page on . Rates and thresholds change, usually on January 1.
General information for US companies, not tax, legal or accounting advice for yours. Rules and thresholds change; confirm the specifics with a CPA or the agency before you act on them.