It has a brand new battery in it but I did some research for you and it is a standard size 357 battery. I checked a few stores and they are pretty much the same price. The battery would cost about $1.88 to replace. Remember though, you're not going to keep it lit ALL the time are you? You can get a 3 pack for $4.07. I hope this helps. Very good question to ask. You're a pretty smart cookie! Anything else I can help you with, please feel free to ask. Cathy