Connecticut Estate Tax Calculator (2026 Exemption Limits & Inheritance Liabilities)

Connecticut sets its estate tax exemption at $15,000,000, the highest threshold of any state that still taxes estates at the state level, meaning only a small fraction of Connecticut estates ever owe the state anything at all.

Once an estate crosses that line, Connecticut taxes the excess at a flat 12%, one of only two states, alongside Vermont, that applies a single flat rate instead of a graduated bracket structure. That 12% ceiling also ties Maine for the lowest top rate among the twelve states that still run a separate estate tax.

That pairing (a very high exemption with a comparatively modest flat rate) makes Connecticut's system unusual. Most of the other eleven states set a lower threshold, a steeper rate, or both; Connecticut does neither, which keeps its estate tax narrowly targeted at the wealthiest households in the state.

Connecticut does not levy a separate inheritance tax on top of its estate tax, so once the state estate tax is calculated, no beneficiary owes the state anything further. Returns are typically due nine months after death, with a six-month extension available for estates that need more time to value real estate, business interests, or other illiquid holdings.

Estate tax obligations are computed by evaluating gross worldwide estate assets less allowable marital, charitable, and administrative deductions against state exemption floors.

### Statutory Mathematical Formulation $$\text{State Estate Tax} = \begin{cases} 0 & \text{if } \text{Net Estate} \le \text{Exemption} \\ \sum_{j=1}^{K} \text{Taxable Tier}_j \times \text{Rate}_j & \text{if } \text{Net Estate} > \text{Exemption} \end{cases}$$ $$\text{Net Distributable Estate} = \text{Gross Estate} - \text{State Estate Tax} - \text{Administrative Costs}$$

### Computational Execution Steps: 1. Gross Estate Valuation: Fair market valuation of all worldwide real property, business interests, equities, cash, and life insurance proceeds. 2. Allowable Deductions: Subtraction of debt obligations, administrative expenses, qualifying charitable bequests, and unlimited marital deductions. 3. Exemption Threshold Comparison: Net estate value is compared against Connecticut's statutory exemption floor. 4. Bracket Tier Allocation: Assets exceeding the exemption threshold are taxed across progressive state rate tiers. 5. Tax Credit Offsets: Application of state gift tax credits or prior transfer credits where permitted by statute.

1. Start with the gross estate. This example uses a $5,000,000 gross estate: the fair market value of all property, business interests, equities, cash, and life insurance the decedent owned at death, before deductions.
2. Compare against Connecticut's exemption. Connecticut taxes estates only above $15,000,000; the $5,000,000 estate sits at or below that threshold, so none of it is taxable.
3. Taxable estate above exemption. $5,000,000 minus the $15,000,000 exemption leaves nothing above the line, so the taxable estate above the exemption is $0.
4. Compute the tax due. With nothing above the exemption, the calculator returns $0.00 in Connecticut estate tax, even though Connecticut's top bracket reaches 12.0% above the threshold.
5. Distribute the net estate. The full $5,000,000.00 gross estate passes to beneficiaries undiminished.
6. What this leaves out. This is Connecticut's state-level result only; federal estate tax is assessed separately under IRC § 2010.

Sophisticated estate planning in Connecticut utilizes established legal and actuarial vehicles: - Irrevocable Life Insurance Trusts (ILITs): Holding life insurance outside the taxable estate provides liquidity to pay estate taxes without subjecting death benefits to taxation. - Spousal Lifetime Access Trusts (SLATs): Removing appreciated assets from the gross taxable estate while preserving indirect spousal access to trust distributions. - Grantor Retained Annuity Trusts (GRATs): Transferring future asset appreciation to beneficiaries free of gift and estate taxes above the statutory Section 7520 hurdle rate. - Charitable Remainder & Lead Trusts (CRTs / CLTs): Generating immediate income tax deductions while structuring philanthropic distributions and wealth transfer.

• IRC § 2010 & § 2058: Federal unified exemption rules and state death tax deductions against federal estate liabilities.
• Portability of Deceased Spousal Unused Exemption (DSUE): Federal portability rules allow surviving spouses to utilize unused exemption; state-level portability varies by jurisdiction.
• Irrevocable Trusts & Dynasty Planning: Utilization of Spousal Lifetime Access Trusts (SLATs), Grantor Retained Annuity Trusts (GRATs), and Charitable Remainder Trusts (CRTs) to mitigate state tax exposure.
• Valuation Discounts: Application of minority interest and lack of marketability discounts for privately held family limited partnerships (FLPs).

• Federal generation-skipping transfer (GST) tax under IRC Chapter 13.
• Ancillary probate requirements for real property situated in other jurisdictions.
• Complex liquidity discounts for minority non-voting family business entities.
• State-specific inheritance taxes levied directly on beneficiaries (e.g. PA, NJ, MD, KY, NE).

• Assuming State Exemption Matches Federal: Forgetting that states like Oregon ($1.0M) and Massachusetts ($2.0M) tax estates far below the federal threshold.
• The "Cliff" Effect in Specific States: Failing to recognize that states like New York eliminate the exemption entirely if the estate exceeds 105% of the threshold.
• Out-of-State Real Property Exposure: Holding real estate in states with active estate taxes exposes non-resident estates to proportional state estate taxes.
• Failing to Fund Revocable Living Trusts: Assets held outside trust structures are subjected to public probate proceedings and statutory executor fees.

• Connecticut Department of Revenue / Taxation: Estate Tax Guidance (2026).
• Tax Foundation: State Estate and Inheritance Taxes (2025/2026).
• American College of Trust and Estate Counsel (ACTEC): State Death Tax Comparative Chart.