The head of a hospital is saying to the hospital’s clients: pay five hundred riyals for twenty medical exams in one year, whether for cases of sickness or for regular check-ups throughout the year. If a person uses all twenty exams, he has got what he paid for, but if he does not use them because he did not come for check-ups or did not get sick, he will not get any of his money back.
Praise be to Allaah.
We put this question to Shaykh Muhammad ibn Saalih al-‘Uthaymeen, may Allaah preserve him, and he answered as follows:
Have they agreed on a specific number?
Then it is OK.
Even if he does not come for all twenty appointments, whether because he doesn’t get sick or he is lazy and doesn’t come for check-ups, so the five hundred riyals are gone?
That means he has forfeited his right.
Yes, so if he gives up his right, for example, that’s OK?
It is OK so long as what he has given up is a known amount. And Allâh knows best.
Muhammad ibn Saalih al-‘Uthaymeen