In Islam, the burial should take place as soon as possible. Accordingly, Muslims strive to bury their dead in no more than 24 hours.
Unlike other religions, where it’s okay to delay the burial so that the deceased’s friends and relatives can gather, Islam favours a fast burial.
This partially stems from the days when a lot of diseases and sanitary issues were caused by dead bodies. So, in order to protect the living, Muslims always performed a speedy burial.
However, there were some exceptions to the rule that still apply to this day. In most cases, if the deceased is suspected of dying from an unnatural cause, the burial can be delayed.
For instance, if the Muslim was killed or if foul play is suspected, the burial can wait until the cause of death is determined. Once the suspicions have been cleared or confirmed, the body should then be buried without delay.
Not per se, but it’s best to bury the deceased no more than three days after the death.
Of course, that doesn’t apply if the body requires to be examined by forensic examiners.
For instance, when Colonel Gaddafi died, his body had to be put on display to convince people he was dead. After that, there were investigations into the cause of his death, which took more time. And there were even discussions on how his body should be buried.
Nevertheless, this rarely happens. Even when Osama bin Laden was killed, his body was washed, shrouded, and disposed of at sea in no longer than 24 hours.