As of the census of 2000, there were 4,182 people, 1,497 households, and 881 families residing in the city. The population density was 1,795.2 people per square mile (693.0/km²). There were 1,723 housing units at an average density of 739.6/sq mi (285.5/km²). The racial makeup of the city was 74.99% White, 4.78% African American, 3.35% Native American, 0.41% Asian, 0.07% Pacific Islander, 12.46% from other races, and 3.95% from two or more races. Hispanic or Latino of any race were 50.96% of the population.
There were 1,497 households out of which 25.9% had children under the age of 18 living with them, 41.1% were married couples living together, 13.8% had a female householder with no husband present, and 41.1% were non-families. 37.3% of all households were made up of individuals and 19.4% had someone living alone who was 65 years of age or older. The average household size was 2.25 and the average family size was 2.95.
In the city the population was spread out with 20.9% under the age of 18, 9.3% from 18 to 24, 31.1% from 25 to 44, 21.2% from 45 to 64, and 17.5% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 133.1 males. For every 100 females age 18 and over, there were 141.1 males.
The cost of living is well below the national average making Walsenburg and Huerfano County very attractive for current and future retiree's looking for a pristine area with spectacular natural beauty with a low cost of living.