He passed away at around 6pm on Sunday evening (June 10) at his mother's home in Sikeston, Missouri.
His passing comes just one year after another contestant, Dr Brandon Rogers, 29, was killed in a vehicle accident weeks before his AGT audition was due to air on TV.
Local news provider KFVS reported that Scott County Coroner Scott Amick said a "health condition" had been responsible for Neal's death, while TMZ notes that he had an existing condition "related to his heart".
Boyd ascended to fame after his successful run on America's Got Talent. The opera singer was only 42 years old.
His cause of death was revealed to be heart failure, kidney failure, as well as liver disease.
Past America's Got Talent victor Neal E. Boyd has died.
GETTYNeal Boyd dead The singer with judges Piers Morgan Sharon Osbourne and David Hasselhoff
Neal Evans Boyd was born November 18, 1975, and grew up in Sikeston.
He went on to record his first album My American Dream after winning the show.
"It was a very, very, very bad wreck", Boyd told the Southeast Missourian in February.
He and his mother were still recovering from a auto accident in 2017. "[Recovery is] a very slow progress".
He was also very involved in politics and campaigned for a Missouri District 149 House Seat in 2014. "I shattered a lot of bones, and shattered my hip, which has left me nearly unable to use that leg for now", he told the outlet in February.
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