Mason Pendrous's family will never know how he died

A coroner's report into the 19-year-old University of Canterbury student's death has just been released.

Coroner Sue Johnson says they know he died two to four weeks before his body was discovered in late September.

But she says because of decomposition the cause can't be determined.

Johnson says she can't rule out whether Mason might've been ill in his room before he died.

She says it's an issue she'll consider during her inquiry into the circumstances around his death.