Many growers take their jade plants outside in the summer so they can benefit from the full spectrum of sunlight. If they are not careful, however, the chilly nights of fall can sneak up unexpectedly and a quick frost will freeze the plant tissues. Any frozen tissue will become soft and mushy and will die. Before you throw out the whole plant, try pruning it and see if it will come back. The jade plant is very resilient, and it will usually bounce back from most damage.
Squeeze the stems of the jade plant to check the firmness. Anything that is not firm is probably killed. Cut it off at the first portion where the stem gets firmed up. Check the outermost leaves, as they will probably have taken the brunt of the freeze, and clip off all the soft ones. The jade plant leaves hold a lot of water and the shiny skin seals the water in. This leaves the plant very susceptible to frost damage since freezing expands water and bursts the plant cells.
Cut anything that start wilting and dying in the next few days. Make the cut at a growing point, such as a bud or branch. If the whole upper part of the plant is wilting, then probably the damage is too extensive and your jade plant will die. As long as some of the plant is living, you can expect new growth to show up in four to six weeks.
Water and fertilize the plant and bring it in to a warm and sunny window. Make sure it also has several hours of darkness each night for respiration. As weeks pass, you might notice a few more areas showing signs of frost damage. Just trim those off, cutting them back to the next bud. This will force the energy back into the dormant buds, causing new leaves to sprout.