This completely depends on the quality and type of rechargeable battery, the age of the flashlight (batteries get worse at keeping a charge over time, though how quickly this happens depends on the battery), but most of all, how much it is getting used. Many of the flashlights on this list can go for a year without a recharge if not used at all. That could mean that if you just use the flashlight a few times a year for a few minutes, you might only need to charge it up twice a year. If you are using the flashlight every day for multiple hours, you’ll need to charge it a couple times a week, since most have a max range of 15 hours on lower settings, and half that or less on higher settings.