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FY 2027 mill rate · Fairfield County, CT
Darien property tax rate
Darien's FY 2027 mill rate is 16.05 mills of assessed value. A property assessed at $300,000 owes $4,815.00 for the year. That ranks 158th highest of Connecticut's 168 municipalities, among the lowest tenth, 11.42 mills below the 27.47 mills state median.
- 1Mill rate 16.05 mills
- 2Bill on $300,000 assessed $4,815.00
Your Darien tax bill
The bill before exemptions and credits; fire, sewer or tax district rates are billed on top where they apply. Compare every Connecticut rate.
What Darien's 16.05 mills means
A mill is $1 of tax for every $1,000 of assessed value, so 16.05 mills on a $300,000 assessment is $4,815.00. Connecticut assessments are not market values: "an assessment is equal to 70% of the fair market value of real estate", fixed at the town's last revaluation, which state law requires at least once every five years (Town of Westport Assessor's Office, Frequently Asked Questions). A $300,000 assessment therefore stands for a house valued at about $428,571 when the town last revalued. The FY 2027 rate is levied on the grand list of October 1, 2025 and pays for the year July 2026 to June 2027.
Darien applies the same 16.05 mills to motor vehicles as to real estate and personal property. Fire, sewer and special tax districts inside a town are separate rows in the state's file and are billed on top of the town rate only where the property lies in the district; they are not added here.
Darien's rate in FY 2026 and FY 2027
The mill rate rose 0.57 mills (3.68%) from 15.48 mills in FY 2026, and the same $300,000 assessment owes $171.00 more than at last year's rate. In FY 2026 Darien ranked 161st. With no change in assessments, a higher mill rate passes straight through to the bill.
Tax on common assessed values in Darien
| Assessed value | FY 2027 bill | At the FY 2026 rate | Versus CT median rate |
|---|---|---|---|
| $200,000 | $3,210.00 | $3,096.00 | −$2,284.00 |
| $300,000 | $4,815.00 | $4,644.00 | −$3,426.00 |
| $400,000 | $6,420.00 | $6,192.00 | −$4,568.00 |
| $500,000 | $8,025.00 | $7,740.00 | −$5,710.00 |
| $750,000 | $12,037.50 | $11,610.00 | −$8,565.00 |
Each bill is the assessed value divided by 1,000 and multiplied by 16.05, before exemptions, credits or district charges. These are assessed values, not sale prices: at 70% the $300,000 row is a property valued at about $428,571 at the last revaluation. The last column is the difference from the same assessment at the 27.47 mills state median.
How Darien compares in Fairfield County and Connecticut
Among the 23 municipalities in Fairfield County, Darien ranks 20th highest; the county median is 27.95 mills, so Darien sits 11.90 mills below it. The next higher rate in the county is New Canaan at 16.967, and the next lower is Shelton at 15.51. Statewide, 5% of municipalities have a lower mill rate than Darien.
Outside Fairfield County, the closest rates are Old Saybrook (15.77, Middlesex), Cornwall (16.62, Litchfield), Goshen (16.70, Litchfield), Old Lyme (16.86, New London). Every Connecticut town assesses at 70% of value, but at different revaluation dates, so a town that revalued recently can show a lower mill rate on higher assessments.
Appealing a Darien assessment
In Connecticut the first step is the town's own Board of Assessment Appeals. A written application on the October 1 grand list is due on or before February 20 (CGS § 12-111); for the October 1, 2025 grand list that was Friday, February 20, 2026. The Board holds hearings at which the owner or an attorney or agent must appear in person (CGS § 12-113), and an owner still aggrieved may appeal to the Superior Court within two months (CGS § 12-117a). The question is the assessment's 70% relationship to value at the revaluation date: on Darien's rate, each $10,000 of assessment costs $160.50 a year.
The Connecticut appeal page sets out each step with its source and the ratio arithmetic. This is a summary of the published procedure, not legal advice.
Darien property tax questions
What is the property tax rate in Darien, CT?
Darien's FY 2027 mill rate is 16.05 mills of assessed value; motor vehicles are taxed at 16.05 mills. Source: Connecticut Office of Policy and Management.
How much is the property tax on a $300,000 assessment in Darien?
$300,000 ÷ 1,000 × 16.05 = $4,815.00 a year, before exemptions and credits. At the FY 2026 rate the same assessment owed $4,644.00.
Is Darien's tax rate high for Connecticut?
It ranks 158th highest of 168, among the lowest tenth of Connecticut municipalities; the median is 27.47 mills.
How do I appeal a Darien property assessment?
Application to the town's Board of Assessment Appeals: by February 20 (CGS § 12-111). Then: hearing before the board (March or April (set by the Board)); appeal to the superior court (Within two months of the Board's decision).
Source: Connecticut Office of Policy and Management, Mill Rates for FY 2014-2026 (data.ct.gov dataset emyx-j53e), town-wide rows; county and 2020 population from Wikipedia, List of towns in Connecticut . Appeal steps: Town of Pomfret, Board of Assessment Appeals Application to Appeal (October 1, 2025 grand list); Town of Westport Assessor's Office, Frequently Asked Questions. Last checked October 21, 2026. This page explains published figures; it is not tax or legal advice.