James K Clausen (Postmaster)
james.k.clausen@usps.gov
121 Castle Pines Ave
Johnstown, CO 80534
Johnstown, CO 80534
The Johnstown Post Office is located in the state of Colorado within Weld County. This location serves 11,301 Johnstown residents with a median income of $72,730. It's estimated that approximately 18,038 packages pass through this post office each year.