I think I've read here that you should only store feed for 2 months. That being said I've kept mine for up to 6 months without problem. I think it would depend on where you are located. If you are in a very humid climate or are storing in a wet area that could significantly decrease your storage times. If you are worried about it can you split feed with someone, buy smaller quantities, or store in a freezer? Never feed wet or moldy feed.