Property Tax Calculator

What a mill rate change would mean for your tax bill

  • MILL RATE FY 2025-26
  • ACS 2024 RELEASE
  • PULLED 2026-08-10
Mill rate 29.92 mills Posted real estate and personal property rate, FY 2025-26. This town posts a separate motor vehicle rate. A mill is $1 of tax per $1,000 of assessed value; Connecticut assesses at 70% of market value. A posted rate cannot be compared with another town’s, or with this town’s own rate across a revaluation — the equalized rate beside it can. CT OPM Mill Rates (emyx-j53e).
Equalized mill rate 19.11 millsRANK 115 / 169 11% above the statewide median of 17.18 mills The levy restated against the market value of the town’s property, FY 2022-23. CT OPM Municipal Fiscal Indicators (ej6f-y2wf). The equalized rate restates the levy against the market value of the town's property. The posted rate is not comparable between towns or across a revaluation; this one is.
Net grand list $1.61B Assessed value of all taxable property, grand list year 2024. CT OPM Net Grand List by Town (webp-fgt3).
Median household income $122,390 ACS 5-year estimate, 2024 release — a rolling five-year survey average, not a single year. US Census Bureau, table B19013.
Median home value $366,800 ACS 5-year estimate, 2024 release. Owner-reported value, not an assessment. US Census Bureau, table B25077.

Tax impact calculator

Your yearly home tax is assessment × mill rate ÷ 1,000. The numbers below start with Colchester's median home and update as you type. Motor-vehicle and business-property taxes are separate and not included.

Step 1 — Find your assessment

Start typing a street address (e.g. "127 Norwich") and choose a match — or skip this step. Until you do, the calculator shows Colchester's median home: a $198,400 assessment — about $283,000 of market value as of October 1, 2021 (the date current assessments were set), or roughly $400,000 in today's market.

Loading the address list…

Step 2 — Assessment and mill rates

From Step 1, your tax bill, or the town's property lookup. Your assessment is 70% of what the town judged your home was worth at the October 1, 2021 revaluation. Prefilled with the median Colchester home.

FY 2025-26 adopted rate: 29.92.

Starts at the newest revision: +0.51 mills over the current rate, or 30.43 — a figure circulating after the July 28 referendum, not yet confirmed against a published town document. Edit freely as new proposals emerge.

Rates the town has adopted, proposed, or voted on

Round number for comparison — not proposed by anyone

Tax at current rate
Tax at proposed rate
Change per year
Change per month
Percent change

What each proposal so far means for the median home

Median Colchester home: a $198,400 assessment. Your own numbers are in the tiles above. The fixed rows compare against the adopted 29.92; the last row uses both rates you set above, so it matches the tiles.

RateMill rateYearly billChangePer month
Rates the town has adopted, proposed, or voted on
✓ Current (FY 2025-26), adopted29.92$5,936
Newest revision (+0.51 mills)†30.43$6,037+$101/yr+$8
July 28 proposal (rejected)30.97$6,144+$208/yr+$17
May 20 proposal (rejected)32.01$6,351+$415/yr+$35
Round number for comparison — not proposed by anyone
Current +0.75 mills30.67$6,085+$149/yr+$12
Whatever you set above
Your "proposed" rate

† The +0.51-mill revision (30.43) is the figure circulating after the July 28, 2026 referendum; it is not yet confirmed against a published town document, and every rate here is editable if you have the official number. Estimates cover the real-estate line of a tax bill only. Individual exemptions and credits (veterans, elderly/disabled homeowner programs, etc.) are not reflected. Motor vehicles are billed separately at the same mill rate. This is an estimate for understanding a proposal's impact — it is not a bill, and the actual FY 2026-27 rate will be set only after a budget passes.

What about the 2026 revaluation?

Colchester is re-appraising every property as of October 1, 2026 — the first time since 2021. The new values first affect the tax bill due in July 2027. This is separate from the budget referendum happening now.

Home values have climbed since 2021: the typical Connecticut home is worth about 45% more than in late 2021 (federal house-price index, through mid-2026). So most revaluation notices will show a big jump. A big jump in your assessment does not mean a big jump in your tax bill. When every assessment rises, the mill rate gets cut, because the town can only collect what the approved budget allows. It has happened here before: after Colchester's 2006 revaluation, the grand list rose 41% and the mill rate fell from 32.47 to 23.01. What actually moves your bill is how your home's change compares to the town average — and what happens to the budget.

Prefilled with the Connecticut average. Nobody knows their 2026 number yet — this is a what-if, not a prediction.

Possible new assessment
Tax rate if real estate rises 45%
Est. yearly bill at that rate
Vs. the average home
Change from today's bill

Uses the assessment from the calculator above (the median Colchester home unless you picked your address or typed your own). The "tax rate" tile assumes all real estate rises by the 45% state average while motor vehicles and business equipment (about 17% of the grand list, and not part of a revaluation) stay flat, with town spending flat: 29.92 ÷ (1 + 0.827 × 0.452) ≈ 21.78 mills. Because that non-real-estate 17% doesn't rise, homes as a group pick up a slightly bigger slice — roughly +5% even for a home exactly at the average — while car taxes fall. The same tilt happened inside real estate at the last revaluation: Colchester's residential values rose about 22.5% in 2021 while commercial rose about 15.8% (CT OPM grand-list components). Individual results vary a lot — but not without limit. Professional assessment standards require revaluations to be uniform (typical homes within roughly 10-15% of the market), so for an ordinary house, market movement alone rarely lands far from the town average: in Westport's 2025 revaluation, values rose about 60% on average, with neighborhood averages between roughly 57% and 66%, and condos moved differently than single-family houses. The homes that swing much harder than that usually changed physically — an addition, major renovation, or new construction. The real FY 2027-28 rate will depend on Colchester's actual 2026 grand list and the budget adopted that year. State average from the FHFA all-transactions house price index for Connecticut, late 2021 to early 2026.

How budget dollars translate to mills

Approximate conversion using the October 1, 2024 net taxable grand list of $1,605,955,411 (CT OPM): one mill raises about $1.61M in taxes.

A cut or addition to the combined town + BOE budgets, to the extent it flows through to the tax levy. Negative for a cut.

≈ Mill rate change
≈ Per year, median home
≈ Per year, your assessment

Who pays each levy dollar

The mill rate applies to every property class equally, so each class's share of the grand list is its share of any tax increase. At the current 29.92 mills the whole list raises roughly $48M a year — about $35M of it from homes and apartments. Shares are approximate (class totals are before some exemptions); October 1, 2024 grand list, CT OPM.

Property classShare of grand listOf each $1 raisedOf a $1M increase
Homes & apartments73.4%73¢≈ $734,000
Motor vehicles10.2%10¢≈ $102,000
Commercial & other real estate9.3%≈ $93,000
Business equipment (personal property)7.1%≈ $71,000

An approximation, in both directions: budget changes are not one-to-one with the tax levy (non-tax revenues, state aid, and fund-balance use also move), and the FY 2026-27 levy will be set against the October 1, 2025 grand list, which is not yet published — the GL 2024 total is used here. Median residential assessment: $198,400. The class table above shows how each levy dollar splits across homes, vehicles, businesses, and equipment. For scale, the newest revision's +0.51 mills corresponds to roughly $0.8M more raised by taxes than at the current rate; the July 28 proposal's +1.05 mills was roughly $1.7M.

How this works

Your yearly real-estate tax is simple math: assessment × mill rate ÷ 1,000. Your assessment is 70% of what the town judged your home was worth at the last revaluation (October 1, 2021). One mill is $1 of tax for every $1,000 of assessment (glossary).

Where things stand: Colchester's current mill rate is 29.92 (FY 2025-26). The FY 2026-27 budget has not been adopted — proposals were rejected at referendums in May and on July 28, 2026. The May 20 proposal worked out to 32.01 mills and the July 28 revision to 30.97. The newest revision reported since then is a +0.51 mill increase, or 30.43 mills — a figure this page has not yet been able to confirm against a published town document — and the calculator starts there; you can set the "proposed" rate to match whatever the town publishes next.

Typing your address looks up your property in the State of Connecticut's public assessment files — the same data your tax bill is based on. The lookup happens entirely in your browser; nothing you type is stored or sent anywhere.

About the assessment data (please read)

Vintage. Address lookups use the State of Connecticut's most recent statewide assessment file, which reflects the October 1, 2024 grand list. Colchester last revalued property on October 1, 2021, and between revaluations an assessment changes only through new construction, permits, demolition, or appeals — so for most properties this number is identical to the current (October 1, 2025) assessment. If your property changed recently, use the assessment from your July 2026 tax bill or the town's property lookup (MapXpress), which the assessor's office keeps current.

Revaluation ahead. The town's next revaluation takes effect with the October 1, 2026 grand list (assessor's updates). It will reset every assessment for the tax bills that start July 2027, and the mill rate will be recalculated against the new base. Comparisons on this page apply to bills through FY 2026-27.

What has the posted mill rate done?

Colchester mill rate, FY 2007-08 to FY 2026-27

Mill rates are not comparable across a revaluation, and the rust triangles mark the four years Colchester’s tax base reset on its five-year cycle: FY 2007-08, FY 2012-13, FY 2017-18 and FY 2022-23.

What would this home’s bill have been in each past year?

What this home's bill would have been, back to FY 2007-08

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How the estimate is built — and the independent ways each step was measured

Between revaluations a Connecticut assessment is frozen: it changes only through a permit, an appeal, a demolition, or new construction. So a home’s assessment history is a step function. FY 2007-08, the earliest year charted, already sits inside the October 1, 2006 revaluation, so reaching it from today takes three steps — the revaluations of October 1, 2011, 2016 and 2021 (the five-year cycle in CGS §12-62). Each step below was measured up to three ways from state data, depending on which sources reach that year. Where they disagree, the disagreement is the band on the chart.

And after adjusting for inflation?

The same bill in today’s dollars

Loading the sales history…

Inflation adjustment: CPI-U, All Urban Consumers, U.S. City Average, annual averages (BLS series CUUR0000SA0) — the same series and the same fiscal-year convention used on the budget trends page, where a fiscal year carries the calendar year it begins in (FY 2007-08 = CY 2007, FY 2025-26 = CY 2025). CPI-U rose 55.3% across this window. CPI-U measures the household basket; deflators built to measure what towns buy (wages, benefits, contracted services) rose faster over the same years, and are set against the budget on the budget trends page — against those, a bill that looks flat here would look lower. The 2025 annual average is BLS’s published figure for that year, computed without October 2025, which was not collected during the lapse in federal appropriations.

How much did yearly bills go up, home by home?

How much yearly bills went up, home by home

Sources

  • Assessments: 2025 Connecticut Parcel and CAMA Data (October 1, 2024 grand list), with history joined by parcel id from the 2024 extract (GL 2022 and GL 2023) and Connecticut CAMA Data 2022 (GL 2021) — all CT GIS Office via data.ct.gov, retrieved 8/7/2026. The address/assessment file used by this page: colchester_parcels_gl2024.json (no owner information). Statewide parcel-level collection began with the 2021 grand list, so earlier per-property years are not available in any public statewide dataset — which is why the 18-year chart above is labeled an estimate rather than a record.
  • Revaluation: Town of Colchester — Revaluation Updates (October 1, 2026 town-wide revaluation) and the town's Revaluation Q&A (2006 example: grand list +41%, mill rate 32.47 → 23.01). Statewide value change: FHFA All-Transactions House Price Index for Connecticut, from FHFA’s own quarterly state file (507.40 in 2021 Q4 → 736.50 in 2026 Q2, +45.2%). The same series is mirrored on data.ct.gov as kf98-j89e, which runs a quarter behind at a slightly different vintage (507.59 → 720.72 in 2026 Q1, +42.0%); the figures here are the publisher’s. Westport variation example: "The Revaluation: How It Affects Your Taxes" (Feb 2026).
  • Net taxable grand list (for the budget-to-mills conversion): Net Grand List by Town, 2011-2024, CT OPM via data.ct.gov (GL 2024: $1,605,955,411). The same series identifies Colchester's revaluation years, marked on the mill-rate chart: the residential grand list moves 0.7–1.3% in an ordinary year but −4.1% at GL 2016 and +22.5% at GL 2021, the five-year resets required by CGS §12-62. GL 2006 (funding FY 2007-08) predates this dataset and comes from the town's Revaluation Q&A.
  • Mill rates: Mill Rates for FY 2014-2026, CT OPM via data.ct.gov, and Town of Colchester adopted budget books (FY 2007-08 to FY 2013-14; FY 2022-23, which is blank in the state dataset).
  • FY 2026-27 status and proposal rates: Town of Colchester — Budget Information; the 32.01-mill May 20 referendum rate from the First Selectman's Report of May 15, 2026 (32.38 in the April proposed budget, reduced with $600,000 in supplemental state aid); the 30.97 July 28 rate from the town's July 28, 2026 referendum results announcement. The newest revision — +0.51 mills over the current rate, or 30.43 — is the figure circulating after the July 28 referendum and is not yet confirmed against a published town document; it is shown here as an editable starting value and will be re-sourced to the town's budget materials for the next referendum. Every rate in the calculator is editable, so a reader who has the official number can enter it directly.
  • Pre-2021 assessment history (the estimated 18-year bill chart): Real Estate Sales 2001-2023 GL, CT OPM via data.ct.gov — every Colchester sale of $2,000 or more since 2001 with the property's assessed value at the time of sale (4,937 rows as published), used to measure how much a typical assessment moved at each revaluation. Before measuring, Data/fetch_ct_sales.py keeps only residential sales of $20,000 or more with an assessed value of $10,000 or more and a sales ratio between 0.15 and 1.50, so the observation counts behind each factor are smaller than that row count; the exact filters travel with the derived file. Colchester's revaluation years are absent from that listing, because OPM does not publish a sales ratio for a town in the year its values reset. Pulled and reduced by Data/fetch_ct_sales.py; the derived file this page loads is colchester_sales_history.json, and the raw rows are kept at Data/ct_sales/colchester_real_estate_sales.csv. Where CT OPM's residential grand list reaches (2011 onward, webp-fgt3) it is used instead of the sales measurement, and the two are compared on the chart's method table.
  • Current assessments for any single property: Colchester property lookup (MapXpress), maintained for the town by New England Geo Systems.

The data behind these charts

Colchester’s own series behind the charts on this page, as text. Each table names the dataset it came from and the year of every row. The peer towns and group medians the charts also plot are not repeated here; they are in the same source files, linked in the footer.

Posted mill rate by fiscal year

Posted mill rate by fiscal year for Colchester, Connecticut
Fiscal year Real estate and personal property Motor vehicle Grand list year
FY 2013-1430.2830.282012
FY 2014-1530.5730.572013
FY 2015-1630.7630.762014
FY 2016-1730.9130.912015
FY 2017-1832.3732.372016
FY 2018-1932.2832.282017
FY 2019-2032.8432.842018
FY 2020-2132.8432.842019
FY 2021-2233.0533.052020
FY 2022-2326.8226.822021
FY 2023-2427.2227.222022
FY 2024-2528.6728.672023
FY 2025-2629.9229.922024

A mill is $1 of tax per $1,000 of assessed value, and Connecticut assesses property at 70% of market value. A revaluation steps the posted rate down in that year even when the town collects the same amount of tax, so posted rates are not comparable across a revaluation or between towns. Source: CT OPM, Mill Rates (emyx-j53e).

Tax levy by property type, total tax levy and equalized mill rate by fiscal year

Tax levy by property type, total tax levy and equalized mill rate by fiscal year for Colchester, Connecticut
Fiscal year Real property levy Personal property levy Motor vehicle levy Total tax levy Equalized mill rate
FY 2018-19$33,469,335$1,560,410$4,048,779$39,078,52421.49
FY 2019-20$34,283,527$1,666,740$4,166,813$40,117,08021.93
FY 2020-21$34,557,954$1,659,692$4,339,407$40,557,05320.73
FY 2021-22$35,333,703$1,872,866$4,527,341$41,733,91118.53
FY 2022-23not reportednot reportednot reported$43,065,98319.52
FY 2023-24$35,824,237$2,363,050$4,935,850$43,123,13615.52
FY 2024-25$38,084,754$3,374,581$4,992,510$46,451,84515.63
FY 2025-26$39,731,461$3,379,266$4,895,527$48,006,25415.36
FY 2026-27$40,089,114$3,235,054$5,220,763$48,544,931not reported

The three property-type levies are what the town reported billing on land and buildings, on business equipment and other personal property, and on the vehicles on its October 1 list; they sum to the total. Supplemental motor-vehicle bills, for vehicles registered after October 1, are billed separately and are not in the total. Where a year's breakdown reads "Not reported", the state's row for that year was a partial filing or a zero and the total comes from the town's adopted budget instead, which has no breakdown. The equalized rate restates the levy against the market value of the town's property. That is what makes rates comparable between towns and across a revaluation; the posted rate above is not. Source: CT OPM, Tax Levy by Municipality and Special Tax District (he33-brru) and Equalized Net Grand List (8rr8-a322).

Net grand list by assessment class and grand list year

Net grand list by assessment class and grand list year for Colchester, Connecticut
Grand list year Net grand list Residential Commercial Motor vehicle Personal property
2011$1,176,520,440$892,463,500$98,212,900$115,389,290$38,546,180
2012not reported$899,271,650$98,719,300$115,462,104$46,201,296
2013$1,195,815,175$907,484,360$98,797,400$115,959,209$41,857,755
2014$1,201,873,865$916,402,360$100,538,190$117,413,634$40,248,076
2015$1,216,010,210$926,175,520$101,161,940$119,799,940$41,925,360
2016$1,201,704,429$891,544,700$113,677,690$125,157,459$47,283,890
2017$1,213,163,935$902,773,650$111,037,810$127,875,950$48,524,180
2018$1,223,066,888$910,164,380$111,265,260$128,046,930$50,857,828
2019$1,240,099,632$918,131,870$113,180,010$133,464,158$52,904,750
2020$1,261,557,248$928,617,950$116,096,390$138,020,350$57,495,712
2021$1,544,354,077$1,145,075,470$135,683,680$173,431,850$66,714,207
2022$1,602,935,096$1,155,504,000$136,465,605$182,982,520$103,928,091
2023$1,623,422,414$1,169,713,390$136,695,375$175,719,320$118,165,539
2024$1,605,955,411$1,178,392,580$136,097,785$164,423,660$113,362,776

Assessed values, at 70% of market value. The grand list year runs ahead of the fiscal year that taxes it, so a grand list year and a fiscal year on this page are not the same period. Source: CT OPM, Net Grand List by Town (webp-fgt3).

Income and housing by survey release

Income and housing by survey release for Colchester, Connecticut
ACS release Median household income Per-capita income Median home value Median gross rent Population
2021$104,527$48,144$268,900$1,301 ±14415,552
2022$114,505$52,273$315,500$1,276 ±17515,550
2023$118,839$55,820$340,300$1,398 ±14015,505
2024$122,390$60,108$366,800$1,474 ±15315,648

Each release is a rolling five-year average, not a single year, so consecutive releases overlap and should not be read as year-over-year change. Median home value is what owners report to the survey, not an assessment. Gross rent is contract rent plus the estimated cost of utilities and fuels where the renter pays them, so it is not the figure on a lease; it covers renter-occupied units, while median home value covers owner-occupied ones. The number after ± is the 90% margin of error the Census publishes with that estimate. Source: US Census Bureau, American Community Survey 5-year estimates. Median gross rent is ACS 5-year, B25064.