After retiring, Radbourn opened up a successful billiard parlor and saloon in Bloomington, Illinois. Dating back to his playing days, he had always had a reputation for being a bit vain. Radbourn was seriously injured in a hunting accident soon after retirement. He lost an eye in the accident and spent most of the remaining years of his life shut in a backroom of the saloon he owned, too ashamed to be seen after the injury.
After suffering from the effects of syphilis for a number of years, Radbourn died in Bloomington in 1897 and is interred in Evergreen Cemetery. In 1941 a plaque was placed on the back of his (misspelled) headstone, detailing his career.
It is speculated that Radbourn may be the namesake of the charley horse, a painful leg cramp not unlike that from which he suffered.[9]