Are you wondering how I've been able to see Phantom of the Opera for 40 times and counting....the answer is that every time I go, I get discounted tickets. So here's some information that will guarantee a way for you to get tickets to phantom at a discounted price.
Broadwaybox.com is a website that offers discounts to many different Broadway shows. 95% of the time Phantom of the Opera is offered.
TDF and TKTS
Tdf.org is a website that you have to pay membership for, but it is worth it. You can see certain shows for about $40 or less, Phantom of the Opera has been offering discounts for a Tuesday or a Wednesday evening. TKTS is a booth in Times Square where you can purchase tickets at half price the same day of the show.
Read the newspaper and visit your local library
Newspapers will sometimes offer specials or discounts for certain shows, usually they will publish these offers during the beginning of the Spring and Winter Seasons. Your local libraries (if you live in NY) might sometimes display discount coupons called Twofers which will give you a discounted offer on certain shows the library will have coupons for, phantom is almost always one of the shows.
Craigslist will sometimes have an ad posted for someone looking to sell their show tickets last minute. Sometimes this is worth the search you can get tickets cheaper if the person is desperate to get rid of them at the last minute.
Purchase standing room or rear mezzanine seats
Standing room tickets are available if the performance is sold out. I believe they are now up to $26.50, when I bought my standing room ticket a few years ago it was about $20. They will show you a spot to stand in right behind the last row of orchestra seats. If there are seats available that were not taken the usher will show you to those seats sometime during the performance. I've also sat in rear mezzanine seats which are the cheapest. Truthfully the Majestic theatre is somewhat small so if you don't have any vision problems or you bring binoculars you can still see the show pretty well. I don't care about purchasing these seats because I have sat everywhere in the theatre that you could possibly sit, and to me as long as I get to see the show one more time I am happy.