I have a light that stays on until they go in to roost. I only do this because my coop is very dark at dusk and they were originally hesitant to go inside. I finally realized they couldn't see where they were going! Put in a small light and they began to go right in at dusk.
I then turn it off. They sleep at night and don't need the light. I don't need to use the extra electricity and don't need to create a fire hazard in my small coop. Plus, they don't like the light on at night. They "complain" if I leave the light on too long.
So, my vote is light only if you're coop is too dark for them to see to roost and then turn it off. You could always put it on a timer if you're not available to turn it off yourself.
I then turn it off. They sleep at night and don't need the light. I don't need to use the extra electricity and don't need to create a fire hazard in my small coop. Plus, they don't like the light on at night. They "complain" if I leave the light on too long.
So, my vote is light only if you're coop is too dark for them to see to roost and then turn it off. You could always put it on a timer if you're not available to turn it off yourself.