Manuka honey will never expire, spoil or go bad. You could keep it in your cabinet for a 100 years and it will still be suitable for consumption. It’s best to store it at room temperature. It is not necessary to refrigerate Manuka honey after it’s opened. It should be stored away from extreme heat or sunlight. Manuka honey is considered to be a humectant which means that it can absorb moisture from the air so the cap should be on tight after use.
If you store Manuka honey in a cool place below room temperature, it may crystalize. This doesn’t mean that it’s bad or should be discarded. Just heat a pot of water and take it off the stove just before it boils. Then place the entire jar of honey into the warm water. The crystals will revert back to their original form. You can also do this if the consistency of the honey is too thick and you prefer it to be looser.
Never heat, boil or microwave Manuka honey as this could damage the enzymes which contribute to its benefits and natural properties. Even though there is no need to freeze or refrigerate honey, doing so does not cause any harm.