Carreras is to head to the London ceremony in a brief diversion from his international tour, while Domingo has recorded a video message for his fellow Nessun Dorma performer, who is being recognised with a posthumous prize.
Organisers of tomorrow's event have also given a second chance to choirboy Jack Topping, asking him to perform at the Royal Albert Hall, after a scheduled debut last week was axed as a result of a fire alert.
The 11-year-old Liverpudlian schoolboy's slot at a Classic FM concert last week was pulled with minutes to go. Jack said: "I had never been to the the Royal Albert Hall before and I was so excited that I was going to perform there, so when the show was cancelled I was really disappointed. I can't believe I have been given another chance to sing there."
Carreras will present the award to Pavarotti's widow Nicoletta. She said: "It is wonderful that the music industry is honouring Luciano in this way, particularly when we are celebrating the 50th anniversary of his first recording."
Pavarotti had been due to accept the award six years ago but he died before it could be presented.