Connecticut Property Tax Calculator (Assessed Value & Millage Rates)

The average effective property tax rate across Connecticut is 1.66%, among the ten highest effective property tax rates in the country and good for #3 nationally. Nationally, the average effective rate runs close to 1.0%, which puts Connecticut well over one and a half times the national average of roughly 1.0%. That's just above the Northeast regional average of about 1.61%.

Like its neighbors elsewhere in the Northeast, Connecticut relies on property tax as the primary funding mechanism for public schools, emergency services, and county infrastructure, with local taxing authorities setting the actual millage each year.

Connecticut counties handle the mechanics of periodic reappraisal and millage-setting locally, so the statewide average above is a useful benchmark but actual bills still hinge on the specific county, school district, and any exemptions or appeals the owner has filed in a given year.

Connecticut assesses every property at 70% of market value, a ratio fixed statewide, and then lets each town set its own mill rate on top. Because the ratio never varies, the entire spread between a low-tax town and a high-tax one shows up in the mill rate, which is unusually visible here compared with states that hide differences in the assessment.

None of that detail is asked for here. This calculator works one level up, applying Connecticut's average effective property tax rate of 1.66% to the value you enter. That rate is the ratio of property taxes actually paid to home value across the state, so the assessment ratios, caps, and exemptions described above are already baked into it.

Working through it in order:

1. Start from the town's appraisal. Towns revalue on a five-year cycle, and 70% of that appraisal becomes the assessed value.
2. Take off exemptions. Veterans', elderly, and disability exemptions reduce assessed value, and local option credits reduce the bill.
3. Multiply by the effective rate. At 1.66%, a $400,000 home in Connecticut comes to $6,640 a year before any exemption you enter above.
4. Divide by twelve for escrow. That same home works out to $553.33 a month set aside in a mortgage escrow account.
5. Compare it against your own bill. At 1.66% Connecticut ranks third nationally, behind Illinois at 1.92% and New Jersey at 1.89%. Your county's number is the one that governs; this figure tells you whether it is roughly where a Connecticut home of that value ought to land.

Using this calculator's baseline inputs: a $400,000 home in Connecticut, taxed at the state's 1.66% average effective rate (rank #3 of 50 states).

1. Start with the assessed value. The home is assessed at its full $400,000.00 market value, with no homestead exemption applied in this baseline scenario.
2. Apply the effective rate. $400,000.00 × 1.66% = $6,640.00 in annual property tax, Connecticut's statewide average effective rate.
3. Convert to a monthly escrow. Lenders typically collect property tax in twelve equal installments alongside principal and interest: $6,640.00 ÷ 12 = $553.33 per month.
4. Project a five-year hold. At a flat rate, five years of ownership totals $6,640.00 × 5 = $33,200.00, before any reassessment, exemption change, or millage increase.

At 1.66%, Connecticut carries one of the heaviest property tax burdens in the country, ranking #3 of 50 states. That is a real cost to weigh against the purchase price.

Connecticut's tier schedule above is a straight line, not a staircase. There is no bracket edge, exemption cliff, phase-out or cap anywhere in this calculator's Connecticut path: the engine takes market value, subtracts whatever exemption you enter, multiplies by the single 1.66% effective rate, and divides by twelve. Every figure in this section is that one operation run at a different value.

Two rungs of the sweep. Row 5 values the home at $333,333.33 and returns $5,533.33 a year, $461.11 a month. Row 6 is the $400,000 baseline at $6,640.00 a year and $553.33 a month. The $66,666.67 of value between those two rungs costs $1,106.67 a year, which is exactly what row 1 charges on the entire value of a $66,666.67 property.

The marginal figure. Each additional $10,000 of Connecticut market value costs $166.00 a year, or $13.83 a month in escrow. The engine returns $6,806.00 at $410,000 against $6,640.00 at $400,000, precisely $166.00 apart. A revaluation that lifts an appraisal to $450,000 puts the bill at $7,470.00, an $830.00 annual increase for $50,000 of paper value.

The reverse question. Running the sweep backwards from an escrow budget rather than forwards from a price: $361,445.78 of Connecticut market value returns exactly $6,000.00 a year and $500.00 a month. A buyer who has ring-fenced $500 a month for the tax line has roughly $361,000 of Connecticut house available before that line breaks, about $39,000 short of the $400,000 baseline this page opens with.

The mistake this rate invites, priced. Connecticut assesses at 70% of market value and the town mill rate runs against that assessed figure. The 1.66% used here is an effective rate, already the ratio of tax actually paid to full market value, so it belongs on the market number. Feeding it the assessed number instead is the common error: entering $280,000, which is 70% of the $400,000 baseline, returns $4,648.00 and understates the bill by $1,992.00. That 30% shortfall persists at every value on the sweep, because the same 0.70 is being applied twice.

Exemptions, and where this engine's version differs from Connecticut's. A $25,000 entry in the exemption field takes taxable value to $375,000 and the annual bill to $6,225.00, a $415.00 saving. The engine subtracts that entry from market value, whereas a real Connecticut exemption reduces the 70% assessed value, so an exemption quoted in assessed dollars has to be divided by 0.70 before it goes in this field. A $10,000 assessed-value exemption is $14,285.71 of market value, and entered that way the engine returns $6,402.86. Connecticut also has no general homestead exemption open to every owner-occupant, so for most filers this field stays at zero: the Elderly and Disabled Homeowners credit, the state Property Tax Credit against Connecticut income tax, and local veterans' deductions are the real levers here, and none of the three is modelled by this calculator.

• Specific hyper-local county and municipal millage district variations within Connecticut.
• Special assessment or improvement district charges. Some Connecticut municipalities levy additional assessments on benefiting parcels for street, drainage, or sewer improvements on top of the base town and school millage; the specific list of districts varies by municipality.
• Commercial vs residential assessment classification differentials.
• Property tax appeal reductions or localized board of equalization adjustments.

• Confusing Market Fair Value with Assessed Basis: Some jurisdictions assess property at fractional ratios rather than 100% of market value.
• Failing to File Homestead Paperwork: Homestead exemptions are rarely automatic; homeowners must file timely paperwork with the county appraisal district.
• Underestimating Post-Sale Supplemental Assessments: Purchasing a newly constructed or reassessed property often triggers catch-up supplemental tax bills.
• Ignoring Property Tax Appeal Windows: Missing the annual 30-to-60 day statutory protest window forfeits the right to challenge over-assessed property values for that tax year.

• U.S. Census Bureau: American Community Survey (ACS) Real Estate Assessment Benchmark Data. census.gov/programs-surveys/acs
• Connecticut Department of Revenue Services, the official state tax authority for Connecticut rates, rules and forms. portal.ct.gov/drs

Also consulted: Connecticut municipal Assessors' Offices: Property Tax Assessment Guidance.