The former Prime Minister passed away after suffering a stroke, and theatre bosses behind the Billy Elliot stage show considered axing the Monday night performance due to its unflattering references to the politician.
They decided to go ahead with the performance but they asked the audience at London's Victoria Palace Theatre to vote on whether they wanted to keep a controversial song called Merry Christmas Maggie Thatcher in the show.
The musical number, which was composed by Sir Elton John, features the lyrics "We celebrate today because it's one day closer to (Thatcher's) death", but theatre-goers decided not to cut it from the show, with only three voting in favour of a change, according to the Daily Telegraph.
An insider says: "It was taken seriously and debated and finally decided that it would be best to put it to a democratic vote to the audience. It was a near unanimous verdict to keep the song in and go ahead. It was an electric show."
Producers behind another West End play, The Audience, which stars Dame Helen Mirren as Queen Elizabeth II, marked Thatcher's passing during Monday night's performance. Writer Peter Morgan stepped onstage to acknowledge the news before the start of the play, which features actress Haydn Gwynne portraying the late politician.