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2026 year-end checklist

Deadlines and year-end steps for founders, early employees, and angel investors, including Connecticut filings.

  1. Within 30 days

    File the 83(b) election for restricted stock issued to you and keep the IRS online confirmation or proof of mailing.

  2. By Dec 31

    Model ISO exercises against your AMT crossover before the year closes.

  3. By Dec 31

    Document QSBS facts: issuance dates, gross assets, and active-business tests for each round.

  4. By Dec 31

    Track R&D wages, contractors, and cloud costs by project for the credit and §174A.

  5. Before a liquidity event

    Consider gifting QSBS to children or non-grantor trusts to multiply the exclusion.

  6. With the 2026 return

    Make the payroll tax election for the R&D credit on Form 6765, which can be filed only with an original return.

  7. Quarterly

    Pay estimated tax after secondary sales or tender offers.

  8. With the 2026 CT-1120

    Connecticut C corps with $70M or less of prior-year gross income and no tax liability should file Form CT-1120 XCH with a timely return to exchange unused CT R&D credits for cash. The form can't be filed later.

  9. From July 1, 2027

    Angel investors should request a Connecticut Innovations angel credit reservation before investing. Fiscal 2027 credits are fully reserved.

Dates assume a calendar-year taxpayer. Some items require plan documents or elections that only your advisor or plan provider can complete.

Run this checklist with a tax advisor

In a consultation, we look at your cap table position, option grants, and last return, estimate the federal and Connecticut tax on the exercise or sale scenarios you choose, and tell you whether your shares may qualify for QSBS.

Book a free consultation or call (203) 327-4311 The first consultation is free, with no obligation.
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