A boy has been airlifted to hospital after falling off a verandah at his home on the New South Wales central coast this afternoon.

The five-year-old, who was wearing his Superman suit, was found by his mother semi-conscious after slipping over and falling four metres onto grass about 2pm (AEDT) in Wyong.

Paramedics stabilised the boy and he was airlifted by CareFlight to John Hunter Hospital in a stable condition for observation.