New Castle, Delaware

New Castle population, 2020 to 2024

New Castle added 172 residents from July 2020 to July 2024, a change of +3.1%. In the latest year it moved by +129. Among 11 Delaware places of 5,000 or more, that growth ranks 7th; the median place changed by +3.3%. The median place of 5,000+ in Delaware has 13,326 people, so New Castle is 43% of it.

New Castle covers 3.48 square miles of land and 0.04 of water, for 1,642 people per square mile of land. The median Delaware place of 5,000+ has 1,762, so New Castle is close to the typical town.

What county New Castle is in

All of New Castle's residents live in New Castle County, which had 588,093 residents in 2024. New Castle holds 1.0% of the county's population. The shaded shape is on the map above; dots mark the eight nearest places.

ZIP codes in New Castle

1 ZIP Code Tabulation Area (ZCTA) overlaps New Castle by at least 10% of the ZCTA's or the city's land: 19720. ZCTAs are Census approximations of USPS ZIP code delivery areas. The list comes from the 2020 ZCTA to place relationship file, so a city that annexed land after 2020 may reach into ZIP codes not listed here.

Where New Castle is

The Census internal point of New Castle is at 39.670000, -75.566500. Dover, the capital, is 35.5 miles S in a straight line. The nearest larger place is Wilmington, DE (73,176 people), 4.9 miles away. The nearest city of 100,000 or more is Philadelphia, PA, 32.8 miles away.

Daylight in New Castle

At 39.67° N, New Castle gets about 14 h 59 min of daylight around the June solstice and 9 h 22 min around the December solstice, a swing of 5 h 37 min. Figures are sunrise to sunset from the SunCalc model for June 21 and December 21, 2026.

Places near New Castle

The eight nearest incorporated places of 1,000+ in Delaware, measured between internal points. The closest is Wilmington, 4.9 miles away, with 73,176 people.