As of the census of 2010, there were 14,171 people, 6,110 households, and 3,859 families residing in the city. The population density was. There were 6,476 housing units at an average density of. The racial makeup of the city was 95.0% White, 2.5% African American, 0.1% Native American, 0.8% Asian, 0.2% from other races, and 1.3% from two or more races. Hispanic or Latino of any race were 1.3% of the population. There were 6,110 households of which 27.5% had children under the age of 18 living with them, 45.0% were married couplesliving together, 13.0% had a female householder with no husband present, 5.2% had a male householder with no wife present, and 36.8% were non-families. 31.2% of all households were made up of individuals and 14.2% had someone living alone who was 65 years of age or older. The average household size was 2.32 and the average family size was 2.91. The median age in the city was 41.5 years. 20.9% of residents were under the age of 18; 7.4% were between the ages of 18 and 24; 26.5% were from 25 to 44; 26.2% were from 45 to 64; and 19.1% were 65 years of age or older. The gender makeup of the city was 48.4% male and 51.6% female.
2000 census
As of the census of 2000, there were 14,361 people, 6,101 households, and 4,112 families residing in the city. The population density was 5,709.2 people per square mile. There were 6,272 housing units at an average density of 2,493.4 per square mile. The racial makeup of the city was 97.85% White, 0.75% African American, 0.05% Native American, 0.61% Asian, 0.03% from other races, and 0.71% from two or more races. Hispanic or Latino of any race were 0.71% of the population. 18.7% were of Italian, 16.0% German, 12.5% Irish, 9.3% Polish and 7.9% Slovene ancestry according to Census 2000. There were 6,101 households. 25.4% of the households had children under the age of 18 living with them, 52.5% were married couples living together, 11.1% had a female householder with no husband present, and 32.6% were non-families. 28.3% of all households were made up of individuals non-familial related and 14.2% had someone living alone who was 65 years of age or older. The average household size was 2.35 and the average family size was 2.90. The city's age population was spread out with 21.2% under the age of 18, 6.3% aged 18 to 24, 29.4% aged 25 to 44, 21.2% aged 45 to 64, and 21.9% who were 65 years of age or older. The median age was 41 years. For every 100 females, there were 91.8 males. For every 100 females aged 18 and over, there were 87.2 males. The median income per household in the city was $44,107 and the median income for a family was $52,675. Males had a median income of $38,966 versus $27,297 for females. The per capita income for the city was $22,053. About 3.2% of families and 4.5% of the population were below the poverty line, including 6.6% of those under age 18 and 4.9% of those age 65 or over.
Education
Public education in the city is administered by Willoughby-Eastlake City Public School District. Public schools located with the city of Willowick are Royalview Elementary School, and Willowick Middle School. Both of which occupy the same campus. Willowick has a public library, a branch of Willoughby-Eastlake Public Library.
