After the destruction of the CSS Virginia, he was on the CSS Nansemond on the James River and later on the CSS Selma at Mobile Bay in the last year of the war. He then commanded the ironclads CSS Baltic and CSS Nashville.
He surrendered to Union forces in early May 1865 and was soon afterwards paroled.
Simms died in 1884 and is buried at Rock Creek Cemetery in Washington, D.C.. Assistant Navy Secretary of the Navy during the Civil War Gustavus Vasa Fox is also buried there.
Charles Simm's father, John Douglas Simms, was chief clerk of the U.S. Navy and Acting Secretary of the Navy in 1841. His grandfather, Col. Charles Simms was an officer in the American Revolution and Mayor of Alexandria, Virginia.