His trust in her was so great that he even gave her his imperial seal, the Muhar Uza. She was his constant companion and trusted confidante, and their relationship was intense. Indeed, the court historians go to unheard lengths to document the intimate and erotic relationship the couple enjoyed. In their nineteen years of marriage, they had fourteen children together, seven of whom died at birth or at a very young age.

Mumtaz died in Burhanpur in 1631 AD, while giving birth to their fourteenth child. She had been accompanying her husband while he was fighting a campaign in the Deccan Plateau. Her body was temporarily buried at Burhanpur in a walled pleasure garden known as Zainabad,originally constructed by Shah Jahan's uncle Daniyal on the bank of the Tapti River. The contemporary court chroniclers paid an unusual amount of attention to Mumtaz Mahal's death and Shah Jahan's grief at her demise. In the immediate aftermath of his bereavement, the emperor was reportedly inconsolable.

Apparently after her death, Shah Jahan went into secluded mourning for a year. When he appeared again, his hair had turned white, his back was bent, and his face worn. Burhanpur was never intended by her husband as his wife's final resting spot. As a result her body was exumed in December 1631 and transported in a golden casket back to Agra. There it was interred in a small building on the banks of the Yamuna River. Shah Jahan stayed behind in Burhanpur to conclude the military campaign that had originally brought him to the region. While there, he began planning the design and construction of a suitable mausoleum and funerary garden in Agra for his wife. It was a task that would take more than 22 years to complete: the Taj Mahal.