They have been in detention in Pakistan since May last year, when US commandos raided the house where they, bin Laden and several children were staying. The commandos killed bin Laden.
Pakistani interior minister Rehman Malik said the women had been charged in court. They and the children had been living in Pakistan without a visa. The children were free to leave but could stay with their mothers for the duration of the trial.
A legal expert, Hashmat Habib, said the maximum punishment facing the women was five years in jail.
One of their relatives has reportedly visited Pakistan to urge authorities to let them leave the country. The decision to charge them could be a formal part of that process.