Property Tax Delaware: Three County Rates, Reassessment, and Relief for 2027

A typical Delaware homeowner pays $1,768 a year on a median home value of $352,000, according to the Census Bureau, which works out to an effective property tax rate of 0.50 percent. Sussex County sits lowest at 0.32 percent, Kent in the middle at 0.43 percent, and New Castle County highest at 0.71 percent. The Delaware property tax calculator below multiplies your value by the county’s effective rate (the median bill owners report divided by the median home value) and shows how the result compares with the local median bill. Enter current market value, such as a recent purchase price. Your new assessed value from the county works too, since reassessment put every parcel at full market value as of a fixed date.

The Reassessment That Replaced 1970s and 1980s Values

For decades, Delaware bills rested on values nobody had seen at a closing table. Sussex County last reassessed in 1974 and New Castle County in 1983. Kent County, the most recent of the three, taxed 60 percent of what a property was worth on June 1, 1987. In May 2020 the Court of Chancery ruled that those stale rolls violated the Uniformity Clause of the Delaware Constitution, and all three counties hired Tyler Technologies to revalue every parcel.

The new rolls arrived county by county. Kent went first, valuing homes at market as of July 1, 2023, and using them for the tax year that began in mid 2024. Sussex used the same July 1, 2023 valuation date and switched over for 2025. New Castle’s rolls reflect market value on July 1, 2024 and were first billed in July 2025. State law now requires every county to reassess at least once every five years (9 Del. C. 8306, set by House Bill 62 in August 2023), so the base date will keep moving forward.

Reassessment did not raise total collections. Kent cut its county rate from $0.36 to $0.0572 per $100 of assessed value to collect the same revenue, and Sussex describes its reset as revenue neutral. What changed was who pays. In New Castle, residential assessments rose an average of 477 percent while nonresidential ones rose 233 percent, so homeowners picked up a larger share of the same school levy.

Who Levies the Bill: School Districts First

Delaware has no statewide property tax on homes. Your bill combines rates from the school district, the county, and in Kent the county library, each in dollars per $100 of assessed value. The school district share is by far the largest piece. At Kent’s county rate of $0.0572 per $100, the county government’s portion on a $300,000 assessment is only $171.60. Towns such as Newark and the City of New Castle levy and bill their own tax on top.

Kent, New Castle, and Sussex Side by Side

The calculator’s figures come from the Census Bureau’s 2024 five year survey. New Castle owners report a median bill of $2,499 on a median home worth $352,200, which is 0.71 percent. Kent owners report $1,363 on $316,600, or 0.43 percent. Sussex, home to the beach towns, has the highest median value at $382,600 yet the smallest median bill at $1,222, a 0.32 percent ratio.

Worked examples using the calculator’s own numbers:

• New Castle County, $400,000 home: $400,000 times 0.71 percent is $2,840 a year, or $236.67 a month, which is $341 more than the county’s $2,499 median bill.
• Sussex County, $450,000 home: $450,000 times 0.32 percent is $1,440 a year, or $120 a month, $218 above the Sussex median of $1,222.
• Kent County, $300,000 home: $300,000 times 0.43 percent is $1,290 a year, or $107.50 a month, $73 below Kent’s $1,363 median.

One $350,000 house would run $2,485 in New Castle, $1,505 in Kent, and $1,120 in Sussex. One caveat: survey answers span 2020 through 2024, so they mostly describe bills on the old rolls. Since reassessment shifted New Castle’s levy toward homes, estimates there may run low, especially for older houses whose values had lagged furthest.

Split School Rates in New Castle County

The first reassessed New Castle bills, mailed in July 2025, set off a special legislative session. On August 12, 2025 the General Assembly passed House Bill 242, which let New Castle school districts reset their 2025 to 2026 rates as a residential rate and a higher non-residential rate, capped at two times the residential one. After the Delaware Supreme Court cleared the split in November 2025, the county mailed revised bills due December 31, 2025.

House Bill 462 became law without the Governor’s signature on August 5, 2026 (85 Del. Laws c. 420). It lets New Castle’s non-vocational school districts keep a residential and non-residential rate, set after a reassessment or through a referendum, with the non-residential rate at least equal to the residential rate and no more than 1.85 times it. The vocational technical district cannot continue a split beyond 2025 to 2026.

The Senior School Credit and County Exemptions

Senior school property tax credit. Homeowners 65 or older can take 50 percent off the school portion of the bill on their primary residence, up to $500 a year, under 14 Del. C. 1917. No income test applies. Someone who moved to Delaware on or after January 1, 2018 must have been domiciled here for 10 consecutive years first; arrivals from 2013 through 2017 need three years. Apply by April 30. On a $1,500 school bill, half would be $750, so the credit stops at $500.

Disabled veterans. Since tax years beginning May 1, 2022, a veteran with a 100 percent VA disability rating, or total and permanent disability based on unemployability, can receive a credit for the full school tax after three years of Delaware domicile.

County exemptions. New Castle County takes up to $173,000 off assessed value for county tax for owners 65 or older with income up to $65,000 (Social Security excluded) and a July 1, 2024 assessment no higher than $676,000; a separate school exemption of up to $173,000 applies for incomes up to $15,000 single or $19,000 married. The 2026 filing deadline was June 1. Sussex County exempts up to $229,000 of assessed value for owners over 65 or totally disabled whose income other than Social Security is no more than $6,000, or $7,500 married, filed January 1 to April 30. Kent County runs its own income tested senior and disability exemption through its Board of Assessment.

Challenging a New Value Before the Board of Assessment Review

Each county has one annual appeal window. New Castle’s deadline is March 14, and a referee may hear a residential case and recommend a value to the Board of Assessment Review. Kent’s is the last working day of January, and Sussex opens its window each January (March 31 for the 2026 tax year). Bring comparable sales or an appraisal tied to your county’s valuation date, not today’s market. In New Castle, only the owner, an employee of an owning entity, or a Delaware licensed attorney may represent you at a hearing. A Board decision can go to Superior Court within 30 days.

September 30, the New Castle Exception, and Monition Sales

Delaware bills once a year. In Kent and Sussex the full amount is due September 30, and after that date state law adds a 1.5 percent penalty each month (9 Del. C. 8604). New Castle normally uses September 30 as well, but Senate Bill 228 pushed its 2026 bills to a mid November mailing with payment due December 31, 2026 and penalties starting January 1, 2027. The 2025 special session also cut New Castle’s late penalty on school taxes to 1 percent a month.

Unpaid taxes can be collected through a monition: the county files in Superior Court, the sheriff can sell the property, and the owner may redeem within 60 days after the court approves the sale by paying the price plus 15 percent and costs (9 Del. C. 8722 and 8729).

What the Next Five Year Cycle Means for These Figures

Census releases will increasingly capture bills built on the new rolls, and we refresh the three county ratios with each five year release, usually in December. Meanwhile the five year reassessment clock is already running: each county’s next countywide revaluation is due within five years of the date its board certified the current roll, so base dates will move again before long. Before budgeting for 2027, check your parcel’s assessed value and school rate with the county.

Sources: Census Bureau ACS 2024 5-year data (median real estate taxes paid, B25103, and median home value, B25077); Delaware Code Title 9, sections 8306, 8604, 8722, and 8729, and Title 14, section 1917; Delaware Department of Finance; House Bill 462 and Senate Substitute 1 for Senate Bill 228 (153rd General Assembly); New Castle, Kent, and Sussex county assessment and finance offices. Verify your assessment and bill with the New Castle County Office of Finance, the Kent County Receiver of Taxes, or Sussex County Treasury.