The city is located at the center of Coldwater Township, though it is politically independent.
Coldwater is at 41°56′25″N 85°00′02″W/41.94028°N 85.00056°W/41.94028; -85.00056. The ZIP code is 49036 and the FIPS place code is 17020. The elevation is 969 feet above sea level.
As of the census of 2000, there were 12,697 people, 4,058 households, and 2,520 families residing in the city. The population density was 1,562.5 per square mile (603.0/km²). There were 4,370 housing units at an average density of 537.8/sq mi (207.5/km²). The racial makeup of the city was 85.35% White, 8.42% African American, 0.75% Native American, 0.92% Asian, 0.03% Pacific Islander, 1.52% from other races, and 3.01% from two or more races. Hispanic or Latino of any race were 4.52% of the population.
There were 4,058 households out of which 32.9% had children under the age of 18 living with them, 43.6% were married couples living together, 12.9% had a female householder with no husband present, and 37.9% were non-families. 31.9% of all households were made up of individuals and 13.9% had someone living alone who was 65 years of age or older. The average household size was 2.49 and the average family size was 3.11.
In the city the population was spread out with 22.4% under the age of 18, 9.4% from 18 to 24, 35.4% from 25 to 44, 20.3% from 45 to 64, and 12.5% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 101.5 males. For every 100 females age 18 and over, there were 100.8 males.
The median income for a household in the city was $33,913, and the median income for a family was $41,107. Males had a median income of $31,577 versus $22,088 for females. The per capita income for the city was $15,833. About 6.0% of families and 9.6% of the population were below the poverty line, including 11.6% of those under age 18 and 7.9% of those age 65 or over.
Memorial Airport serves general aviation only.
Coldwater public bus transportation is provided by Branch Area Transit Authority (BATA).
Coldwater has an east-west railroad, but this is practically a relic of one that led to Chicago and Toledo, Ohio.