The Kabir Khan directorial, which stars Saif Ali Khan and Katrina Kaif, collected Rs.8.46 crore on its opening day.
It witnessed a 51 percent growth on the day of Rakshan Bandhan on Saturday, earning Rs.12.78 crore, taking the total to Rs.21.24 crore, said a statement from the production house.
With no big release alongside, `Phantom` is expected to witness growth over the weekend due to the buzz around the movie.
`Phantom`, which revolves around global terrorism, is an adaptation of the novel "Mumbai Avengers".
At least 166 people were killed when terrorists from Pakistan sneaked into Mumbai in November 2008 and went on a killing spree.