The Philippine Idol Semifinalists consisted of 12 aspiring singers who competed for Philippine Idol, but were unable to secure a spot in the Top 12 Finalists. They were selected after several stages of audition and theater eliminations. The semi-finalists were then divided by gender and the two groups alternately performed at SM Megamall Cinema 3, where a stage was specially built for the live shows.
Each semi-finalist sang one song of their choice and received comments from each of the judges. The viewers voted for their favorites by dialing a toll-free telephone number or sending an SMS as many times as possible until 8:30 p.m. the following day.
The top 4 contestants of each group entered the Top 12. Then ten of the remaining 16 then performed in a Wildcard round, with the Top 4 completing the Top 12. Candidates for the Wildcard was announced after the second Semi-Finals Results Show, although it was shown a week later.
The following were not called to be among the finalists during the Semi-Finals and were shut out of the Wildcard Round, therefore eliminating them completely from the competition.
The following were chosen by the judges to perform in the wild card round, but did not make it to the Final 12. The announcement was made public on September 11, 2006.