The year-old cow fell about 200 feet from the cliff and landed on the hood of the couple's minivan, causing heavy damage.
A Chelan County fire chief, Arnold Baker, said the couple missed being killed by a matter of inches in the accident Sunday on a highway near Manson.
The Eversons, visiting the area from their home in Westland, Mich., to celebrate their first wedding anniversary, were checked at Lake Chelan Community Hospital as a precaution.
Everson, 49, said he didn't see the cow falling and didn't know what happened until afterward.
He said he kept repeating: "I don't believe this. I don't believe this."