Estate tax worksheet

Connecticut Estate Tax Calculator (2026)

For a 2026 death, Connecticut's schedule is 12% of the Connecticut taxable estate above $15 million, up from a $13.99 million exemption for 2025 deaths. Lifetime taxable gifts, property allocation and gift-tax credits can change the result, and an estate below the exemption still files Form CT-706 NT with the Probate Court. This worksheet follows the state return through its liability and payment lines.

Updated Oct 6, 20267 primary sources citedEditorial policy

Connecticut estate and gift-tax worksheet

Who this covers and what to enter

For deaths in 2026 and 2027, using prepared Form CT-706/709 amounts. Enter whole dollars. Resolve asset inclusion, QTIP elections, gift overlap and eligibility for credits before using this calculation.

Date of death Confirmed residency Connecticut gross estate — line 5 ($)Prepared Schedule D total, including required gift-tax and QTIP additions.Connecticut deductions — line 6 ($)Prepared Schedule E total; exclude the federal deduction for state death taxes.Taxable gifts in the year of death — line 8 ($)Schedule A; exclude gifts already included in gross estate.2005–2025 Connecticut taxable gifts before the year of death ($)Prepared prior-year gifts from January 1, 2005, through the year before death. Exclude gifts already in gross estate; enter gifts in the year of death separately. The 2026 return reports this on Schedule B and line 9; confirm the applicable return for a 2027 death.Property for the selected allocation ($)Resident: real/tangible property outside Connecticut (Schedule F line 2). Nonresident: qualifying Connecticut property (Schedule G line 3).Prepared prior Connecticut gift-tax credit — line 14 ($)Use the adjusted Schedule B credit; this is not the value of gifts.Allowed Connecticut Innovations credit — line 16 ($)Enter the prepared credit, not the original investment.Connecticut gift tax paid on gifts made since January 1, 2016 ($)This reduces the $15 million lifetime tax cap separately from the gift-tax credit.Prior payments for this return — line 19 ($)Include applicable extension payments; do not repeat the gift-tax credit. I have confirmed the prepared state amounts, domicile and qualifying property. Any Schedule B overlap adjustments and QTIP elections are resolved. I understand this excludes federal tax, probate fees, interest and penalties.

Your estimate

Needs your figuresCalculated

Select residency and confirm the prepared amounts.

Estimated liability — line 18: —
Connecticut taxable estate — line 10: —
12% schedule before allocation: —
Tax before credits — line 13: —
Resident property credit — line 15: —
Remaining lifetime tax cap: —
Balance before interest / penalties: —
Estimated overpayment: —

The property fraction rounds to four decimals. Tax lines use whole-dollar estimates. A zero tax estimate does not settle the return requirement or probate fee.

Reviewed October 1, 2026 against the 2026 Form CT-706/709 and June 2026 line instructions. Parameters and probate-court filing rules rechecked October 6, 2026 against the 2026 Form CT-706 NT instructions.

Connecticut estate tax parameters for 2026 deaths

Parameter	Connecticut rule	Applies to	Primary source
Exemption amount	$15,000,000 of Connecticut taxable estate; $13,990,000 for 2025 deaths	Deaths during calendar year 2026	CT-706 NT instructions; 2025 line instructions
Rate	12% of the excess over the federal basic exclusion amount	Deaths during calendar year 2026	2026 estate tax table
Gifts in the base	Connecticut taxable gifts made on or after January 1, 2005 that are not already in the federal gross estate, plus Connecticut gift tax paid on gifts the decedent or spouse made in the three years before death	Every Connecticut taxable estate	CT-706 NT instructions
State death-tax deduction	The federal deduction for state death taxes (IRC § 2058) is disregarded	Every Connecticut taxable estate	CT-706 NT instructions
Lifetime tax cap	$15 million, less Connecticut gift tax paid on gifts made on or after January 1, 2016	Section 3, line 18 of the 2026 return	Line 18 instructions
Return due	Six months after death; Form CT-706/709 EXT asks for nine more months to file or six more months to pay	Taxable estates (CT-706/709 with DRS)	When to file
Nontaxable estates	Form CT-706 NT, filed with the Probate Court within six months, not with DRS	Taxable estate of $15 million or less with no Connecticut QTIP election	CT-706 NT instructions

Why two $20 million estates can owe different amounts

With no deductions, gifts, credits or allocation adjustment, a $20 million Connecticut taxable estate produces a $600,000 schedule amount. Change only the location of qualifying property and the result changes:

Illustration	Property adjustment	Estimated Connecticut liability
Resident; all property in Connecticut	$0 credit	$600,000
Resident; $5 million eligible property outside Connecticut	0.2500 × $600,000 credit	$450,000
Nonresident; $5 million eligible Connecticut property	0.2500 × $600,000 allocated tax	$150,000

These calculated examples hold gross estate at $20 million and all other entries at zero. A property address alone does not resolve classification. Schedules F and G use different property numerators, both divided by Connecticut gross estate; their fractions round to four decimals. Schedules F and G.

Gifts: three entries with different jobs

Current-year taxable gifts and prepared prior-period gifts increase the tax base. The prior gift-tax credit reduces tax. Gift tax paid on gifts made since 2016 also reduces the remaining lifetime tax cap. These amounts are not interchangeable. Gifts already in gross estate require the Schedule B worksheet adjustments before entry. Gift overlap and cap instructions.

For example, a $14 million prepared estate plus $2 million of taxable gifts produces a $16 million base and $120,000 schedule amount. Entering the estate alone would show zero. A valid $30,000 gift-tax credit would then reduce that example to $90,000 before any other adjustment.

The tax cap is not the exclusion

Both figures are $15 million in this return year, but they limit different things. The exclusion removes the first $15 million of taxable estate from the 12% schedule. The lifetime cap limits tax liability after credits, reduced by specified gift tax already paid. Section 3, line 18.

A $200 million base has a $22.2 million schedule amount. With no credits and no cap already used, this worksheet limits liability to $15 million. If $1 million has already used the cap, the remaining ceiling is $14 million. Those are model illustrations, not predictions about a particular estate's deductions or credits.

Prepare the Connecticut amounts first

Schedule D can add gift taxes associated with gifts within three years of death and Connecticut QTIP property. Schedule E excludes a deduction for state death taxes and handles state QTIP deductions. A nonresident's qualifying Connecticut property can include certain pass-through holdings; mortgage debt does not reduce the real-property value used in Schedule G. Schedules D, E and G instructions.

The form separates taxable estate, credits, prior payments and overpayment. This calculator preserves that separation. It does not decide which assets belong in an estate, create an election, determine an investment credit or estimate probate fees. Return lines and schedules.

Does zero tax mean no filing?

No. At or below the threshold, the instructions direct the estate to Form CT-706 NT for the appropriate probate court, except where a Connecticut QTIP election requires CT-706/709. The estate return is generally due six months after death. Electronic filing and payment use myconneCT. Filing instructions · Current forms and extensions.

Connecticut asks for a return even when no tax is due

Form CT-706 NT must be filed for every decedent who was a Connecticut resident at death, and for a nonresident who owned real or tangible personal property located in Connecticut. A resident's return goes to the Probate Court for the district where the decedent lived; a nonresident's goes to the district where the property is. The court must physically receive it within six months of death; a postmark does not count. An estate claiming the decedent was a nonresident also files Form C-3 UGE, the Connecticut domicile declaration. CT-706 NT filing rules.

The return needs the death certificate, the recorded deed for any Connecticut real property and the signed federal Forms 706 and 709 when those were filed. When the gross estate is $15 million or less it also needs schedules valuing every asset, including any assets allocated to the surviving spouse for the Connecticut marital deduction. The probate judge then either issues an opinion of no Connecticut estate tax due on Form PC-255 or directs the estate to file Form CT-706/709 with DRS. The Probate Court issues the release of lien on real property for a nontaxable estate; DRS issues it for a taxable one. Connecticut does not require a consent to transfer for intangible personal property.

Probate fees are a separate charge with a separate base. Schedules H and I use the greatest of the probate inventory, the Connecticut taxable estate and the federal gross estate, and count property passing to the surviving spouse at half. A resident's real or tangible property outside Connecticut is left out; a nonresident's base counts only such property located in Connecticut. This worksheet does not compute the fee. Schedules H and I.

Federal tax needs a coordinated calculation

Do not simply add a federal estimate calculated before state death-tax deductions to this state result. Federal Form 706 has its own deductions, gift-tax computation and any available deceased-spouse unused exclusion. Federal Form 706 instructions.

Compare New York's estate-tax cliff, Massachusetts estate tax or Illinois's interrelated calculation. Each uses a different state method.

Using the verified 2027 structure

For a 2027 death, the published federal basic exclusion replaces $15 million in the same 12% formula. The lifetime $15 million tax cap remains separate. Enter the actual IRS amount when available; the calculator does not forecast it. CGS 12-391(g)(9) and cap provisions.

First documented August 26, 2026 · Updated October 6, 2026