According to citrus fruit vendors Pittman & Davis, it's possible to freeze grapefruit and maintain good quality. The grapefruit should be peeled and the white pith stripped off, then the fruit should be put into a plastic bag. When frozen, grapefruit remains edible for up to one month.
At the time of purchase, grapefruit needs to be free of dents and soft spots. The entire fruit ideally feels firm to the touch. Grapefruit remain fresh for only about six days at room temperature, although this varies depending upon the initial ripeness of the fruit. When refrigerated, they last for two weeks if kept free from moisture.