According to the United States Census Bureau, the city has a total area of 5.6 square miles (14.6 km²), of which, 5.6 square miles (14.4 km²) of it is land and 0.1 square miles (0.2 km²) of it (1.07%) is water.
The Kent County side of Milford was first settled in 1680 by Henry Bowan on what was known as the Saw Mill Range. A century later the Reverend Sydenham Thorne built a dam across the Mispillion River to generate power for his gristmill and sawmill. Around the same time, Joseph Oliver laid out the first city streets and plots nearby on a part of his plantation. Soon a number of homes and businesses appeared along Front Street and Milford was born. The city was incorporated February 5, 1807.
In the 1770s, a ship building industry was already flourishing on the Mispillion River. Shipbuilding continued to be the major industry of Milford through World War I, bringing considerable prosperity to the town. The high point came in 1917 when the four-masted, long Albert F. Paul was launched from the William G. Abbott shipyard. At one point six shipyards were operating in the downtown area. When the last of the area’s giant white oaks was cut in the 1920s, the shipyards quickly went out of business, although the Mispillion ships sailed on for many years. (The Paul was sunk by a German torpedo in 1942 while sailing from the Bahamas.) The Vineyard shipyard was called into service in both WW I and II to build submarine chasers.
During much of the twentieth century Milford served primarily as the commercial center for much of southern Delaware's large agricultural community.
Seven of Delaware's governors came from Milford: Daniel Rogers (who served 1797-99), Joseph Haslet (1811-14), William Tharp (1847-1851), Peter F. Causey (1855-59), William Burton (1859-63), William T. Watson (1895-97) and Ruth Ann Minner (2001-present).
On Friday, May 30th, 2003 at approximately 3:00 p.m. a fire started in a second floor apartment next to Wiley Hardware & Appliance on Walnut Street in the historic downtown section of Milford. More than 200 firefighters from Milford, Ellendale, Harrington, Felton, Dover, Smyrna, Houston, Frederica, Slaughter Beach, Bowers Beach, Greenwood, South Bowers, Farmington, Magnolia, Cheswold, Lewes, Georgetown, and Bridgeville in Delaware and Greensboro and Goldsboro in Maryland fought the blaze which destroyed seven businesses, a church, and three apartments, destroying an entire city block in the historic section of town. No one was killed in the blaze, but one civilian and six firefighters were injured.
There were 2,665 households out of which 32.6% had children under the age of 18 living with them, 42.6% were married couples living together, 16.8% had a female householder with no husband present, and 36.2% were non-families. 31.2% of all households were made up of individuals and 15.5% had someone living alone who was 65 years of age or older. The average household size was 2.44 and the average family size was 3.03.
In the city the population was spread out with 27.2% under the age of 18, 9.5% from 18 to 24, 27.3% from 25 to 44, 18.3% from 45 to 64, and 17.7% who were 65 years of age or older. The median age was 35 years. For every 100 females there were 86.6 males. For every 100 females age 18 and over, there were 80.1 males.
The median income for a household in the city was $32,525, and the median income for a family was $40,333. Males had a median income of $29,271 versus $23,164 for females. The per capita income for the city was $16,181. About 10.4% of families and 14.4% of the population were below the poverty line, including 21.1% of those under age 18 and 12.6% of those age 65 or over.
The city of Milford has a crime rate higher than the national average in some categories, much higher in rape, assault, and theft, and lower in others.