Jon William Koster

Jon William Koster, age 57, of St. Ansgar, Iowa, passed away on Wednesday June 25, 2025. Jon was born to Jack and Shirley (Mouw) Koster on Sept. 7, 1967. Jon married his soul mate Jean Heimer on September 4, 1993. Jon and Jean made their home in St Ansgar, where they raised their two sons Jackson and Garrett. Jon graduated from Iowa State University with a B.S. in Agronomy. Following graduation, he worked in agriculture running K2Ag as well as helping Jean run Thymeless Treasures for the last 22 years.

Jon was an avid outdoorsman enjoying time hunting and fishing. Some of his favorite hunting memories include guiding elk hunters in Colorado, a special Alaskan caribou hunt with his brother Jeff, and a moose hunt down the Kantishna River with a story only he could tell. Jon never let Garrett forget that he's the only one in the family to catch a 6lb Smallmouth. Jon was also a Minnesota Vikings season ticket holder for over 20 seasons and enjoyed taking the family to games every year. Jon was kindhearted, generous, and always willing to give to someone in need.

He loved his family more than anything in the world and was extremely proud of his two sons. He will be dearly missed by Jean, Jackson, Garrett and all of his family and friends.

Jon was preceded in death by his mother Shirley, father Jack, brothers Jeff and Steven (infant), and Uncle Bill.

A Mass of Christian Burial will be held at 2:00pm on Tuesday July 1, 2025, at Visitation Church in Stacyville, Iowa with Rev. Raymond A. Burkle officiating. There will be a visitation period from 11:00am to 2:00pm on Tuesday before mass at church. Private family interment will be in St. Ansgar City Cemetery. In lieu of flowers, memorials are preferred to the Wounded Warrior Project, Sons of the American Legion, or St. Jude.

Hoff Celebrations – Schroeder Chapel of St. Ansgar is assisting the family with arrangements.