tw telecom in Oshkosh, WI
These numbers are located in the city of Oshkosh part of Winnebago county. There are a few other subcodes that cover this area as well so take care not to confuse them.
Winnebago county is situated in Wisconsin and operates CT (UTC -06:00) time. This number group covers the 54901, 54904, 54906, & 54903 zip codes.