51104 is zip code located in Sioux City, Iowa. The population is 21,878, making 51104 the 2nd largest zipcode in Sioux City and the 2nd largest in Woodbury County.
There are 5 public schools in 51104 with an average Homefacts rating of C+. The total crime rate for Sioux City is moderate , and there are 47 registered sex offenders residing in the zip code 51104. Unemployment in 51104 is moderate.