Buying and Selling: Claiming Payment After the Deferment Period in a Credit Transaction

Practical Laws of Islam as per the teachings of Ayatullah Sistani

Ruling 2117

If a commodity is sold on credit, the seller can claim the payment for it from the buyer after the completion of the agreed deferment period. However, if the buyer is unable to pay, the seller must give him respite or annul the transaction and take back the commodity if it still exists.

-Ayatullah Sistani, Practical Laws of Islam, Buying and Selling