Ronald “Ron” Koester, 90, passed away on April 5, 2026. He was born on September 3, 1935, to Fred Koester and Mattie Nutzman Koester in Idaho Falls, Idaho. Ron will be laid to rest at Fielding Cemetery on April 13, 2026. This will be a true homecoming, as Ron grew up harvesting potatoes on the family farm at this exact site.

Ron is survived by his loving wife of 68 years, Shirley Waters Koester; his children, JoAnn Koester, Connie Koester, and Bill Koester; his two granddaughters, Kellie Koester and Kacie Koester; and two great-grandsons, Conrad Wall and Kingston Wall. He is preceded in death by his parents, Fred and Mattie Koester, and his three brothers, Edward, Dale, and Glen Koester.

Ron graduated from Idaho Falls High School in 1953 and from the University of Idaho in 1957. Ron married the love of his life on August 1, 1957, in Lava Hot Springs, Idaho. They had three children in three years and embarked on a full family life. Ron put his Bachelor of Agricultural Science to good use working for Simplot Soil Builders before transitioning into finance in 1966. Ron attended brokerage training in New York City, and he took his first stock brokerage job with Goodbody Brokerage Firm in 1966. He retired 52 years later from D.A. Davidson. Ron loved his job, especially his many clients, and his family fondly remembers watching the stock report with him daily.

Ron was an active member of the Masonic Lodge Eagle Rock #21, the Order of Eastern Star Chapter #85, and the First Presbyterian Church. He enjoyed going for drives, boating on Palisade Lake and in Yellowstone National Park, puzzles, card games, and walking his dogs. Ron was a true and loyal friend and dedicated himself to his family, friends, and clients.

In lieu of flowers, please donate to either the Idaho Falls Community Food Bank online at https://feedidahofalls.org/donations/ or to the Development Workshop online at https://www.dwinc.org/donation-form/ or to a charity of your choice.

Funeral services will be held at 1:00 p.m., Monday, April 13, 2026, at the First Presbyterian Church, 325 Elm Street, Idaho Falls. The family will visit with friends and family from 6-8:00 p.m., Sunday, April 12, 2026, at Coltrin Mortuary, 2100 First Street, Idaho Falls, and one hour prior to services at the church. Interment will be at Fielding Memorial Park Cemetery. Online condolences may be sent to www.coltrinmortuary.com.