Overview
New Castle County is home to 573,030 people (Census ACS 5-Year, 2023), making it Delaware's most populous county by a wide margin. It accounts for roughly two-thirds of the state's residents and ranks higher than 96% of U.S. counties by population. The county seat is Wilmington, the state's largest city and a major corporate hub.
Median household income sits at $89,901 (Census ACS 5-Year, 2023), well above the national median of roughly $75,000 and higher than 92% of U.S. counties. Per capita income follows the same pattern at $46,990 (Census ACS 5-Year, 2023). The county's housing vacancy rate is just 5.2% (Census ACS 5-Year, 2023), lower than 95% of counties nationally, a sign of tight supply in a populated metro area.
Demographics
New Castle County skews younger than most of the country. Median age is 39.2 (Census ACS 5-Year, 2023), lower than about 71% of U.S. counties.
The population is racially mixed. White residents make up 53.5%, Black residents 24.6%, Hispanic residents 11.4%, and Asian residents 5.9% (Census ACS 5-Year, 2023). The Black population share is higher than 88% of U.S. counties. The Asian population share, at 5.9%, ranks higher than 96% of counties nationally. Native residents account for 0.1% (Census ACS 5-Year, 2023).
Education attainment is strong. 39.2% of residents hold a bachelor's degree or higher (Census ACS 5-Year, 2023), placing the county above 91% of U.S. counties. That's roughly ten percentage points above the national average. A well-educated labor force tracks with the county's concentration of corporate headquarters and financial services firms.
Education
New Castle County's public schools spend $20,229 per pupil (Education Data Portal, 2020), about 35% above the national average of roughly $15,000. Total enrollment is 77,876 students (Education Data Portal, 2021), reflecting the county's size.
The student-teacher ratio is 13.9:1 (Education Data Portal, 2021), slightly better than the national average of about 15.5:1. Smaller class sizes correlate with the higher spending.
The graduation rate is 87.8% (Education Data Portal, 2019), close to the national average of roughly 87%. For a county that spends significantly more per student and maintains smaller classes, a graduation rate at the national mean raises questions about where those dollars are going and whether outcomes match the investment.
Economy & Employment
The labor force totals 309,998 people, with 294,604 employed (BLS LAUS, 2025). The unemployment rate is 5.0% (BLS LAUS, 2025), higher than 81% of U.S. counties. That rate sits above the national average and is the highest among Delaware's three counties.
Income tells a different story. Average adjusted gross income per return is $88,969, and average total income is $89,725 (IRS Statistics of Income, 2021). Those figures rank above 90% of counties nationally. The county processed 279,480 tax returns with total AGI of $24.9 billion (IRS Statistics of Income, 2021).
The poverty rate is 9.9% (Census ACS 5-Year, 2023), lower than about 74% of U.S. counties. For a county with high incomes, that's a notable gap. Nearly one in ten residents lives below the poverty line even as the median household pulls in close to $90,000. Income distribution is uneven.
Mean commute time is 21.4 minutes (Census ACS 5-Year, 2023), shorter than 57% of U.S. counties. Most residents work within the county or in nearby Philadelphia and Baltimore metro areas.
Housing & Cost of Living
Median home value is $329,800 (Census ACS 5-Year, 2023), higher than 88% of U.S. counties. That's roughly 3.7 times the median household income, a ratio that puts homeownership within reach for many middle-income households but still represents a stretch for those closer to the median.
Median gross rent is $1,379 per month (Census ACS 5-Year, 2023), above 91% of U.S. counties. Fair market rent data from HUD (2026) is available for the county, though specific bedroom-level breakdowns were not included in this dataset.
The county has 235,057 total housing units, with 12,114 vacant (Census ACS 5-Year, 2023). That 5.2% vacancy rate is extremely low, lower than 95% of U.S. counties. Tight inventory puts upward pressure on both rents and home prices. For renters spending $1,379 a month, the math leaves limited room for saving toward a down payment on a $330,000 home.
Health & Wellness
New Castle County's health picture is better than most of the country on several measures. Only 11.6% of residents report poor physical health (CDC PLACES, 2023), a rate lower than 89% of U.S. counties. The obesity rate is 33.4% (CDC PLACES, 2023), lower than 83% of counties nationally.
Cholesterol screening rates are high at 86.2% (CDC PLACES, 2023), above 92% of U.S. counties. Annual checkup rates hit 77.6% (CDC PLACES, 2023). These numbers suggest residents have relatively good access to preventive care.
The uninsured rate is 8.9% (CDC PLACES, 2023), lower than about 71% of counties. Depression affects 21.5% of adults, and 16.3% report poor mental health (CDC PLACES, 2023). Both figures sit in the lower quartile nationally, meaning fewer residents report these conditions compared to most counties.
High blood pressure affects 32.1% of adults, and diabetes affects 10.7% (CDC PLACES, 2023). The diabetes rate lands near the national midpoint, while blood pressure runs slightly below. Chronic disease prevalence is moderate.
Climate & Natural Disasters
Hurricanes account for eight of the county's 17 federally declared disasters since 1965 (FEMA OpenFEMA, 2026). That's nearly half, and it shapes how to think about risk here. The most recent federal declaration came in October 2021.
Temperatures are mild. The annual average is 55.1°F, with highs at 64.5°F and lows at 45.6°F (NOAA Climate Data Online, 2025). Annual precipitation runs 40 inches and snowfall averages 14.7 inches (NOAA Climate Data Online, 2025), both near the national middle.
Snowstorms account for four of those 17 declarations, so winter isn't without disruption. With fewer disasters than 67% of U.S. counties (FEMA OpenFEMA, 2026), the county sits below the U.S. average. That's not a clean bill of health. Delaware falls squarely in the Atlantic hurricane track, and the historical record says storms will keep coming. June through November is the window to watch.
Financial Profile
The banking footprint in New Castle County is enormous. FDIC records show 4,214 bank branches holding $897.9 billion in total deposits (FDIC Summary of Deposits, 2023). These figures rank at the very top nationally, higher than virtually all U.S. counties. Delaware's status as a banking incorporation state inflates these numbers considerably. Many major banks are chartered in the state, and their deposits are recorded here regardless of where the physical branches operate.
Average AGI per tax return is $88,969 (IRS Statistics of Income, 2021), above 90% of counties. Total AGI across all returns reaches $24.9 billion (IRS Statistics of Income, 2021), reflecting both high individual incomes and a large filing population.
Social Security beneficiaries total 112,910 (SSA OASDI, 2024). That's roughly 20% of the county's population, consistent with a county where the median age sits below 40 and the workforce is large relative to retirees.
Key Comparisons
New Castle County consistently ranks in the top 10% of U.S. counties across income, education, and population metrics. A few comparisons stand out.
Income and housing track together. The county's median household income of $89,901 is higher than 92% of counties, and its median home value of $329,800 is higher than 88% (Census ACS 5-Year, 2023). The home value-to-income ratio of about 3.7x is manageable compared to coastal metros where it can exceed 8x or 10x.
Health outcomes are favorable. Obesity, poor physical health, and poor mental health rates all land in the bottom quartile nationally (CDC PLACES, 2023). High screening and checkup rates suggest the health infrastructure is reaching most residents.
The unemployment rate is the weak spot. At 5.0% (BLS LAUS, 2025), it's higher than 81% of counties, a surprising figure for a county that otherwise ranks so well on economic measures. This could reflect structural mismatches between the county's corporate economy and segments of the population without the education or training to access those jobs.
Within Delaware, New Castle County leads on income, education, and labor force size. It also has the lowest vacancy rate and shortest commute time among the state's three counties. It carries the highest poverty rate in the state (Census ACS 5-Year, 2023), a reminder that aggregate prosperity can mask concentrated need.
Data Sources
- Census ACS 5-Year, 2023: Population, income, housing, demographics, education attainment, commute times, poverty rate
- BLS LAUS, 2025: Unemployment rate, labor force, employment counts
- CDC PLACES, 2023: Health metrics including obesity, diabetes, mental health, insurance coverage, preventive care
- HUD Fair Market Rents, 2026: Data not available for New Castle County
- FEMA OpenFEMA, 2026: Disaster declarations and history
- IRS Statistics of Income, 2021: Tax returns, adjusted gross income, total income
- FDIC Summary of Deposits, 2023: Bank branch counts and total deposits
- NOAA Climate Data Online, 2025: Temperature and precipitation averages
- SSA OASDI, 2024: Social Security beneficiary counts
- USDA Census of Agriculture, 2022: Data not available for New Castle County
- Education Data Portal, 2021: Per-pupil spending, enrollment, student-teacher ratio, graduation rate