It was Britt's second trial. The first trial, in 2006, ended in a jury deadlocked 11 to 1 when one juror refused to take part in deliberations.
Tuesday the jury in the second trial unanimously agreed Britt was guilty. The state was seeking the death penalty.
Britt was charged with killing his wife, Nancy, who was a popular Wake County teacher, in August 2003 at her sister's home. She had been shot in the abdomen and died of internal bleeding.
At the 2006 trial, prosecutors argued that Myron Britt was in financial trouble and wanted to collect $800,000 in life insurance on his wife.