The by-elections that are going to be held after July 25 general elections would be one of the most expensive by-polls in the history of Pakistan.
Several politicians, including the several heads of their parties, are contesting elections on multiple seats.
At least 50 national and provincial assembly seats will be left empty after the July 25 polls.
The candidates who are contesting elections on more than one seat will have to leave their other seat(s), if they manage to win more than one.
PTI chairman Imran Khan is contesting elections on five national assembly seats. His rival PML-N president Shehbaz Sharif is contesting polls on four national assembly seats.
Bilawal Bhutto Zardari, the young PPP chairman, is contesting elections on three national assembly seats, while Dr Farooq Sattar, one the few MQM-P heavyweights is contesting elections on three national assembly seats.