Connecticut Estate Tax Guide

Connecticut runs its own estate tax, and the line sits high. For a death on or after January 1, 2023, an estate owes nothing unless the Connecticut taxable estate passes the federal exclusion amount, which is $15 million for a 2026 death (Conn. Gen. Stat. § 12-391(g)(9)). Above that line the rate is a flat 12 percent of the excess. Connecticut charges no inheritance tax.

Most families land far under the line and still have to file. Conn. Gen. Stat. § 12-392(b)(3)(J) requires a return for every decedent who died a Connecticut resident, and for every nonresident who owned Connecticut real property or tangible personal property. The only open question is which of the two returns you file, and where it goes. Here is how the exemption works, what the six-month deadline covers, and why the estate tax lien is the reason so many inherited houses sit unsold.

Does Connecticut Have an Estate Tax? Yes

Conn. Gen. Stat. § 12-391(d)(1)(E) taxes the transfer of the estate of anyone who died a Connecticut resident on or after January 1, 2019. Subsection (e)(1)(D) reaches a nonresident, taxing Connecticut real property and tangible personal property with an actual situs here.

The rate schedule for a current death has two rows and no graduated bands. Section 12-391(g)(9) charges nothing on a Connecticut taxable estate at or below the federal exclusion amount, and 12 percent of the excess above it. Only the excess is taxed. A 2026 estate with a $16 million Connecticut taxable estate pays 12 percent of the $1 million overage, so $120,000 before credits, not 12 percent of the whole $16 million.

That flat structure replaced the graduated tables Connecticut used through 2022. Check the schedule for the actual date of death rather than the current one, because the older bands are still live law for older estates.

The Exemption Moves With the Federal Number

Connecticut stopped writing its own dollar figure. Section 12-391(c)(4) defines the federal exclusion amount as the dollar amount the Internal Revenue Service publishes annually at which a decedent would have to file a federal estate tax return, and § 12-391(g)(9) keys the whole schedule to it. The Connecticut number now changes every January without any further act of the General Assembly.

For 2026 the IRS puts that amount at $15,000,000, up from $13,990,000 for a 2025 death. The Department of Revenue Services says the same thing on its estate and gift tax page: for estates of decedents dying during 2026, the Connecticut exemption is $15 million.

Here is what the last several years look like, drawn from § 12-391(g) and the matching filing thresholds in § 12-392(b)(3):

Quoting today's $15 million figure for a 2021 death overstates the exemption by nearly $8 million and produces a filing answer that is wrong in both lanes.

The Other $15 Million Is a Ceiling on Tax, Not on the Estate

Two different rules use the same number, and collapsing them is the most common error published about Connecticut.

Section 12-391(d)(1)(E) says that for a death on or after January 1, 2019, the tax payable may not exceed $15,000,000, reduced by Connecticut gift tax paid on gifts made on or after January 1, 2016 that come back into the gross estate. The Department of Revenue Services states the same cap on the aggregate of Connecticut gift and estate tax payable for calendar years beginning on or after January 1, 2019.

One $15 million figure describes an estate size at which tax starts. The other describes a tax amount at which the bill stops growing. At a flat 12 percent, the ceiling only bites around $140 million of Connecticut taxable estate. Almost nobody meets it.

What Goes Into the Connecticut Taxable Estate

Section 12-391(c)(1)(C) builds the number in three parts:

• The gross estate less allowable deductions, as determined under Chapter 11 of the Internal Revenue Code.
• Plus all Connecticut taxable gifts the decedent made in calendar years beginning on or after January 1, 2005, other than gifts already inside the federal gross estate.
• Plus any Connecticut gift tax paid to the state by the decedent or the estate on a gift made by the decedent or the decedent's spouse during the three years before death.

The deduction for state death taxes under Internal Revenue Code § 2058 gets disregarded.

The gift add-back matters more in Connecticut than anywhere else, because Connecticut is the only state with a stand-alone gift tax (Conn. Gen. Stat. § 12-642). Two decades of Connecticut taxable gifts come back into the estate calculation, so a giving history changes the answer.

Federal deductions still apply. Section 12-391(f)(1) preserves every deduction available under the Internal Revenue Code, including the qualifying income interest for life under § 2056(b)(7), and subsection (f)(2) lets an executor make that election for Connecticut purposes whether or not one was made federally. The Department of Revenue Services adds two conditions: a Connecticut-only election is available only when no federal election was made, and it has to go on Form CT-706/709 rather than Form CT-706 NT.

Two Filing Lanes, and Every Estate Uses One

Section 12-392(b)(2) says a return counts as filed only when it reaches the Probate Court for the district where the decedent lived, and the Commissioner of Revenue Services as well when subdivision (3) calls for it. For a nonresident, the court is the one for the district where the Connecticut property sits. Connecticut has no county probate court, so the venue follows the decedent's town, not a county line. The Connecticut probate guide walks the district question in full.

Three things trip people here.

Do not mail Form CT-706 NT to the Department of Revenue Services. The department says so directly, and § 12-392(b)(3)(J) confirms that nothing goes to the commissioner when the Connecticut taxable estate sits at or below the exemption.

The judge reviews what you file. Section 12-392(b)(3)(J) makes the judge of probate read each return and issue a written opinion to the estate representative in every case where the estate owes no tax. That opinion is the document a bank or title company usually wants.

A small estate does not escape the return. The affidavit path for a modest Connecticut estate settles the probate side. It does nothing about the estate tax return, which § 12-392(b)(3)(J) still requires.

The Deadline Is Six Months, Not Nine

Section 12-392(a)(1) makes the Connecticut tax due at the date of the taxable transfer and payable at the expiration of six months from the date of death for anyone who died on or after July 1, 2009. The return is filed on or before that same date under § 12-392(b)(1), figured without regard to any extension of time to pay.

Miss it and the arithmetic is unpleasant. The penalty is 10 percent of the amount due and unpaid or $50, whichever is greater, and interest runs at 1 percent per month or fraction of a month from the due date until payment. The department says interest cannot be waived, though § 12-392(a)(1) lets the commissioner forgive the penalty where the failure was for reasonable cause and was not intentional or due to neglect. Even a nontaxable estate can draw a $50 penalty for failing to file a required return.

Use Form CT-706/709 EXT to ask for more time to file or to pay. An extension does not stop the meter: § 12-392(a)(2) charges 1 percent per month on any additional tax from the original due date to the date it is actually paid.

The federal clock is different. Returns under 26 U.S.C. § 6018(a) are due within nine months of death (26 U.S.C. § 6075(a)), with Form 4768 available for an extension. Anyone working both returns should mark two dates. The Connecticut probate timeline shows where the six-month tax date lands against the rest of the court calendar, and filing on time is part of the job described in the Connecticut executor duties guide.

Connecticut Has No Inheritance Tax

An inheritance tax charges the person who receives money. Connecticut does not have one.

The old succession tax in chapter 216 sunset. Conn. Gen. Stat. § 12-340(a) now applies the chapter only to estates of people who died on or before January 1, 2005 that, before October 1, 2018, had filed a return under § 12-359 or been assessed a tax under § 12-367. Nothing in that reaches a current death.

One cross-reference keeps the confusion alive. Section 45a-107(b)(1)(i) still measures one of the four possible bases for the statutory probate fee by "the gross estate for succession tax purposes, as provided in section 12-349." That is a surviving pointer inside the fee statute, not a live tax on beneficiaries.

Income is the exception worth remembering. Money an inherited account earns after the death is ordinary taxable income to whoever receives it, and Connecticut taxes that the normal way.

The Estate Tax Lien That Stalls a House Sale

This is the part that surprises families mid-closing.

Section 12-398(d) gives the state a lien on the real property transferred, running from the due date of the tax until it is paid, with interest and costs. The lien is not valid against a lienor, mortgagee, judgment creditor, or bona fide purchaser until notice is recorded in the town clerk's office. Connecticut sets no expiration on it.

Getting it released depends on which lane the estate is in. Section 12-398(e)(1) has the Probate Court issue the certificate of release, unless a return is required with the Commissioner of Revenue Services under § 12-392(b)(3), in which case the commissioner issues it. Section 12-398(e)(2) then has the certificate recorded with the town clerk of the town where the land sits, and that recording is conclusive proof the property is out from under the lien.

For an estate that has to file Form CT-706/709 and holds Connecticut real property, the department requires the estate's Connecticut attorney or corporate fiduciary to apply on Form CT-4422 UGE before the sale. Where payment of the tax is adequately provided for, the department issues a signed and sealed Form CT-792 UGE.

Watch for the second lien. Section 45a-107b gives the Probate Court its own lien on estate real property for the statutory settlement fees, released by the court. Clear both before a closing date, not after. The selling inherited property in Connecticut guide covers the sale itself, and the Connecticut estate tax calculator gives you a fast read on whether the estate is anywhere near the taxable line.

Nonresidents Who Owned Connecticut Property

A nonresident estate computes the tax on the whole Connecticut taxable estate and then multiplies by a fraction: Connecticut-situs gross estate over total gross estate (§ 12-391(e)(1)(D)). Section 12-391(e)(2)(A) limits the state's reach to real property here and tangible personal property with an actual situs here.

For a nonresident dying on or after January 1, 2019, § 12-391(e)(2)(B) looks through certain pass-through entities. Connecticut real or tangible property owned by a partnership, S corporation, or disregarded single-member LLC is treated as owned directly by the decedent when the entity carries on no business for profit, the ownership served no valid business purpose, or the property came in other than by a bona fide sale for full consideration while the decedent kept a power or interest that pulled it into the federal gross estate.

The department adds a filing rule for this group: an estate of someone not domiciled in Connecticut for whom a full estate is opened under Conn. Gen. Stat. § 45a-287 or § 45a-303(a)(2) has to file a Connecticut estate tax return. The Connecticut ancillary probate guide covers the court side of that filing.

Where the Federal Estate Tax Fits

Federal law sets the exclusion at $15,000,000 (26 U.S.C. § 2010(c)(3)(A)), indexed from a 2025 base for anyone dying in a calendar year after 2026 and rounded to the nearest $10,000. Above the applicable exclusion, the rate schedule in 26 U.S.C. § 2001(c) tops out at 40 percent.

Two federal features do not carry into the Connecticut answer.

Portability is the first. Federal law lets a surviving spouse stack the deceased spousal unused exclusion amount on top of the ordinary exclusion (26 U.S.C. § 2010(c)(2)), but only where the first spouse's executor filed a timely estate tax return and made the election (§ 2010(c)(5)(A)). Connecticut points its own definition at the annual IRS figure by itself (Conn. Gen. Stat. § 12-391(c)(4)) and adds no unused spousal exclusion on top, so an inherited federal exclusion does not raise the Connecticut line. Married couples use the Connecticut QTIP election on Form CT-706/709 instead, and the Connecticut surviving spouse rights guide covers the statutory share that sits alongside it.

Lifetime giving is the second. Federal completed gifts leave the taxable estate. Connecticut taxable gifts made since 2005 come back in under § 12-391(c)(1)(C).

What Lowers a Connecticut Bill and What Does Not

Start with what does not work. A funded revocable trust keeps assets out of court and leaves them inside the gross estate, because the grantor kept control during life. The how to avoid probate in Connecticut guide explains the split people miss: probate avoidance and estate tax reduction are separate projects.

What does move the number:

• Out-of-state real and tangible property. Section 12-391(d)(2) reduces a resident estate's tax by the fraction of the gross estate made up of real or tangible personal property located outside Connecticut.
• The marital deduction and a Connecticut QTIP election. Section 12-391(f) carries the federal deductions through, including § 2056(b)(7) property.
• Credit for Connecticut gift tax already paid. Section 12-391(d)(1)(E) credits gift tax the decedent or the estate paid on Connecticut taxable gifts made on or after January 1, 2005, plus gift tax the decedent's spouse paid on the decedent's gifts from that same period where those gifts come back into the gross estate. The credit cannot exceed the tax imposed.
• The private investment fund reduction. Section 12-391(i) cuts the tax by half of what the decedent invested in a qualifying private investment fund under § 32-39(40) and held for ten years or more, capped at $5 million per estate and $30 million across the program, for deaths on or after January 1, 2021.

Whatever the outcome, gather date-of-death values early. The same figures feed the return and the statutory probate fee: § 45a-107(b)(1) computes the fee basis from the greatest of four measures of the gross estate, halves the portion passing to a surviving spouse, and caps the fee at $40,000 once the basis reaches $8,877,000. That is why the court's fee invoice tends to arrive after the return, not at filing.

When to Bring In a Professional

Get help when the estate holds a business interest, farmland, or property in more than one state. Get help when the decedent made Connecticut taxable gifts since 2005 and nobody kept the returns. Get help when a surviving spouse may want the Connecticut QTIP election, because it has to be made on the right form by the deadline and cannot be fixed later.

For a straightforward estate under the exemption, Form CT-706 NT plus supporting date-of-death values is a document-gathering job, not a litigation one. Confirm the values, file with the right Probate Court within six months, and keep the judge's written opinion with the estate file.

Frequently Asked Questions

Does Connecticut have an estate tax?

Yes. Conn. Gen. Stat. § 12-391 taxes the transfer of a resident decedent's estate, and the Connecticut real property and tangible personal property of a nonresident decedent. For a death on or after January 1, 2023, § 12-391(g)(9) charges nothing on a Connecticut taxable estate at or below the federal exclusion amount and 12 percent of the excess above it. The Department of Revenue Services puts that amount at $15 million for a 2026 death.

Does Connecticut have an inheritance tax?

No. The Connecticut succession tax sunset. Conn. Gen. Stat. § 12-340(a) limits chapter 216 to estates of people who died on or before January 1, 2005 that had already filed a return under § 12-359 or been assessed under § 12-367 before October 1, 2018. A beneficiary owes Connecticut nothing for receiving an inheritance. One leftover cross-reference confuses people: § 45a-107(b)(1)(i) still measures part of the probate fee basis by the gross estate for succession tax purposes, which is drafting history rather than a live tax.

Does every Connecticut estate have to file an estate tax return?

Yes, in one lane or the other. Conn. Gen. Stat. § 12-392(b)(3)(J) requires a return for every decedent who died a Connecticut resident, and for every nonresident whose gross estate holds Connecticut real property or tangible personal property. If the Connecticut taxable estate sits at or below the federal exclusion amount, the estate files Form CT-706 NT with the Probate Court for the district where the decedent lived and files nothing with the Department of Revenue Services. Above that amount, Form CT-706/709 goes to the department and a complete copy goes to the court.

When is the Connecticut estate tax return due?

Six months after the date of death. Conn. Gen. Stat. § 12-392(a)(1) makes the tax payable at the expiration of six months from the date of death for anyone who died on or after July 1, 2009, and § 12-392(b)(1) fixes the return on that same date. Late payment carries a penalty of 10 percent of the unpaid tax or $50, whichever is greater, plus interest at 1 percent per month. The federal Form 706 is due at nine months under 26 U.S.C. § 6075(a), so the two deadlines do not share a date.

How do I clear the Connecticut estate tax lien before selling an inherited house?

Conn. Gen. Stat. § 12-398(d) puts a lien on the transferred real property from the due date of the tax until it is paid, with no fixed expiration. Section 12-398(e)(1) has the Probate Court issue the certificate of release, unless the estate had to file with the Commissioner of Revenue Services, in which case the commissioner issues it on Form CT-4422 UGE and returns Form CT-792 UGE. Section 12-398(e)(2) records the certificate with the town clerk where the land sits. Ask for the release before you sign a purchase and sale agreement.

Does a revocable living trust cut the Connecticut estate tax?

No. A funded revocable trust keeps assets out of probate and leaves them inside the gross estate, because the person who created it kept control during life. Lifetime giving does not solve it either. Conn. Gen. Stat. § 12-391(c)(1)(C) adds Connecticut taxable gifts made on or after January 1, 2005 back into the Connecticut taxable estate, along with any Connecticut gift tax paid on gifts made within three years of death.

This guide is general information about Connecticut estates, not advice for your situation.

Sources:

• Title: Conn. Gen. Stat. § 12-391: Transfer of resident and nonresident estates. Definitions. Rate of tax. Determination of domicile. Limit on tax payable. Reduction of tax for investment in private investment fund. Publisher: Connecticut General Assembly. Publication Date: Not listed. URL: https://www.cga.ct.gov/current/pub/chap_217.htm#sec_12-391
• Title: Conn. Gen. Stat. § 12-392: Payment of tax. Penalties for late filing. Extension of time. Interest on overpayment. Method of filing. Notice to court of probate. Publisher: Connecticut General Assembly. Publication Date: Not listed. URL: https://www.cga.ct.gov/current/pub/chap_217.htm#sec_12-392
• Title: Conn. Gen. Stat. § 12-398: Amended return. Additional assessment. Disclosure of return information by court of probate. Tax lien. Certificate of release of lien. Publisher: Connecticut General Assembly. Publication Date: Not listed. URL: https://www.cga.ct.gov/current/pub/chap_217.htm#sec_12-398
• Title: Conn. Gen. Stat. § 12-340: Tax on transfers of property. Sunset of chapter. Publisher: Connecticut General Assembly. Publication Date: Not listed. URL: https://www.cga.ct.gov/current/pub/chap_216.htm#sec_12-340
• Title: Conn. Gen. Stat. § 12-642: Rate of tax. Aggregate limit on tax imposed. Publisher: Connecticut General Assembly. Publication Date: Not listed. URL: https://www.cga.ct.gov/current/pub/chap_228c.htm#sec_12-642
• Title: Conn. Gen. Stat. § 45a-107: Fees and expenses for settlement of decedent's estate. Interest on unpaid fees. Exception. Publisher: Connecticut General Assembly. Publication Date: Not listed. URL: https://www.cga.ct.gov/current/pub/chap_801b.htm#sec_45a-107
• Title: Conn. Gen. Stat. § 45a-107b: Lien on real property for fees imposed in the settlement of decedent's estate. Release of lien by Probate Court. Petition for release of lien. Publisher: Connecticut General Assembly. Publication Date: Not listed. URL: https://www.cga.ct.gov/current/pub/chap_801b.htm#sec_45a-107b
• Title: Estate and Gift Tax Information. Publisher: Connecticut Department of Revenue Services. Publication Date: June 30, 2026. URL: https://portal.ct.gov/drs/individuals/individual-income-tax-portal/estate-and-gift-taxes/tax-information
• Title: Estate and Gift Tax - CT-706 Series. Publisher: Connecticut Department of Revenue Services. Publication Date: Not listed. URL: https://portal.ct.gov/drs/drs-forms/current-year-forms/estate-and-gift-tax-ct-706-series
• Title: Trusts and Estates. Publisher: Connecticut Probate Courts, Office of the Probate Court Administrator. Publication Date: Not listed. URL: https://www.ctprobate.gov/trusts-estates
• Title: 26 U.S.C. § 2001: Imposition and rate of tax. Publisher: Office of the Law Revision Counsel, United States House of Representatives. Publication Date: Not listed. URL: https://uscode.house.gov/view.xhtml?req=granuleid:USC-prelim-title26-section2001&num=0&edition=prelim
• Title: 26 U.S.C. § 2010: Unified credit against estate tax. Publisher: Office of the Law Revision Counsel, United States House of Representatives. Publication Date: Not listed. URL: https://uscode.house.gov/view.xhtml?req=granuleid:USC-prelim-title26-section2010&num=0&edition=prelim
• Title: 26 U.S.C. § 6075: Time for filing estate and gift tax returns. Publisher: Office of the Law Revision Counsel, United States House of Representatives. Publication Date: Not listed. URL: https://uscode.house.gov/view.xhtml?req=granuleid:USC-prelim-title26-section6075&num=0&edition=prelim
• Title: IRS releases tax inflation adjustments for tax year 2026, including amendments from the One Big Beautiful Bill. Publisher: Internal Revenue Service. Publication Date: 2025. URL: https://www.irs.gov/newsroom/irs-releases-tax-inflation-adjustments-for-tax-year-2026-including-amendments-from-the-one-big-beautiful-bill
• Title: About Form 706, United States Estate (and Generation-Skipping Transfer) Tax Return. Publisher: Internal Revenue Service. Publication Date: Not listed. URL: https://www.irs.gov/forms-pubs/about-form-706
• Title: About Form 4768, Application for Extension of Time To File a Return and/or Pay U.S. Estate (and Generation-Skipping Transfer) Taxes. Publisher: Internal Revenue Service. Publication Date: Not listed. URL: https://www.irs.gov/forms-pubs/about-form-4768

It is not legal advice.