Tiffin is a city in Johnson County, Iowa, United States.

[3] F. W. Kent County Park is located just to the west of Tiffin, and is a popular site for outdoor recreation in Johnson County, being noted for its lake, camping facilities, resident whitetail deer herd and wild turkeys, and its cross-country ski trails through rolling acres of oak and hickory forest.

[4] The name was a transfer from Tiffin, Ohio, the former home of Rolla Johnson, who owned the town site.

There were 1,978 housing units at an average density of 476.0 per square mile (183.8/km2).

Hispanic or Latino persons of any race comprised 5.5% of the population.

There were 848 housing units at an average density of 205.3 per square mile (79.3/km2).

27.8% of all households were made up of individuals, and 5.4% had someone living alone who was 65 years of age or older.

There were 457 housing units at an average density of 152.9 per square mile (59.0/km2).

29.8% of all households were made up of individuals, and 5.0% had someone living alone who was 65 years of age or older.