When a Poor Person Performs Hajj and then becomes Wealthy

Q: Hajj -29: Hajj was not Fardh for a poor person, but he was then given some money to perform Nafl Hajj. If he becomes wealthy enough afterwards, will Hajj become Fardh for him?

Answer: If the person made only the intention of Nafl Hajj when he performed Hajj, the Hajj will be regarded as Nafl and he will have to perform Hajj again after he becomes wealthy enough to perform Hajj.1 However, he made the intention to perform his Fardh Hajj or if he did not specify, the Hajj will be regarded as his Fardh Hajj and he will not have to repeat the Hajj when he acquire sufficient wealth. And Allaah knows best what is most correct.

Fatawa Rahimiyyah vol.3