CT Estate Tax Exemption 2026: Thresholds, Rates, and Filing Requirements

Every Connecticut resident estate — and every nonresident estate owning Connecticut real or tangible personal property — must file a state estate tax return, even if it owes nothing. That single fact catches more families off guard than the tax rates themselves, because skipping the filing creates an invisible lien that can block a future sale or refinance of inherited property.

Connecticut's 2026 Estate Tax Exemption

For the 2026 calendar year, Connecticut's unified estate and gift tax exemption sits at $15 million per individual ($30 million for a married couple). This threshold applies to the combined lifetime gifts and assets at death.

If the Connecticut taxable estate and reportable lifetime gifts remain within the available $15 million exemption, no state estate tax is owed. But — and this is the part that trips people up — the filing requirement still applies.

Connecticut Estate Tax Rates

For estates exceeding the $15 million exemption, Connecticut imposes a graduated tax with a top rate of 12% on the taxable portion.

Connecticut is also the only state in the country that maintains a standalone gift tax unified with the estate tax. Lifetime gifts that exceed the annual exclusion ($19,000 per recipient in 2026) count against the $15 million lifetime exemption.

The Mandatory Filing Nobody Warns You About

Here is where Connecticut diverges from nearly every other state: regardless of whether the estate owes any tax, the executor must file the appropriate Connecticut estate-tax return within six months of death. For an estate at or below the $15 million threshold, that is Form CT-706 NT with the local Probate Court. For a taxable estate above $15 million, file Form CT-706/709 with the Department of Revenue Services and a copy with the Probate Court.

This applies to every resident estate and any nonresident estate owning real or tangible personal property within Connecticut.

For a nontaxable estate, the filing triggers three things:

1. The Probate Court reviews the return
2. The court calculates the statutory probate fee
3. The court issues a Certificate of Opinion of No Tax, which formally releases the automatic estate tax lien

The Invisible Tax Lien on Every Connecticut Property

Upon death, Connecticut automatically places a statutory lien on all real property owned by the decedent. This lien is not recorded on municipal land records — it is invisible until someone tries to transfer the property.

The lien can only be released after filing the required estate-tax return and receiving the court's certificate. Without that release, title insurance companies will flag the property, blocking any sale, refinance, or transfer indefinitely.

Families who used trusts or joint tenancy to avoid probate often skip this filing entirely. Years later, when heirs try to sell the home, the unreleased lien surfaces. By then, interest on unpaid probate fees (0.5% per month, or 6% annually) may have accumulated into thousands of dollars.

The Non-Portability Problem

Unlike the federal estate tax system, Connecticut does not allow portability of the estate tax exemption between spouses. If one spouse dies and fails to use their full $15 million exemption, that unused portion disappears permanently.

For couples with combined assets approaching or exceeding $15 million, this means proactive planning through credit shelter trusts or bypass trusts is essential — otherwise the surviving spouse's estate faces full exposure to the 12% state rate.

What This Means for Your Estate Plan

Most Connecticut families will never owe state estate tax at the $15 million threshold. But every family with real property needs to understand the mandatory filing requirement and the invisible lien mechanism.

The Connecticut Estate Planning Kit includes a complete CT-706 NT filing checklist, a property transfer matrix showing which assets trigger the lien, and a timeline tracking all six-month deadlines — so nothing falls through the cracks that could cloud your family's title for years.

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