It seems like a no-brainer to leave the lights on outside your home to deter burglars while you’re away (or even while you’re asleep). But does that really work? Or is it just a waste of electricity — particularly this time of year, when the days keep getting shorter and shorter?

Those answers can differ depending on a number of factors. However, one thing is clear: With more than 1.5 million residential burglaries in the U.S. in 2015, according to the FBI’s Crime in the United States report, it takes more than flipping a switch to prevent property crime.

So, if you are relying on lights as part of your home security routine, be sure to put some thought into how you’re using them. Here are recommendations about when to light things up — and some instances where it may be better to go dark. Contact your local law enforcement if you’re curious about recommendations specific to your area.

When to Keep Your Lights On

There are plenty of instances where it makes sense to leave your porch light on:

• When you’re home (and awake). This doesn’t simply alert people to the fact that someone is home; it allows you to see anyone approaching or prowling around outside. Having a variety of interior lights on, of course, also shows that the home is occupied and not the best target.
• When you go out at night. You’ll be able to get to the door easier and unlock it more quickly when you get home — which is nice, but also important if someone happens to be lurking nearby.
• If possible, combine a porch light with other lights. If you have lighting in your back yard, for example, or by the garage, use those in conjunction with the one by your front door and interior lights. This can add to the appearance that someone is home.

When to Keep Your Lights Off

Despite what many people think, having your lights on all the time isn’t helpful. In fact, it may actually attract burglars. Here’s when you should think about leaving them off:

• When it’s light out. Exterior lights left on all day can give the impression that nobody is home. After all, wouldn’t someone turn them off during the daytime?
• When you’re on vacation. The same principle applies here — if a burglar notices lights on for several days at a time, that’s a pretty clear sign that you’re gone.
• When you go to sleep. This seems counterintuitive, but most residential crime happens during daylight hours, according to SecurAmerica, a firm providing security personnel for businesses, schools and residential communities. So, that porch light at 3 a.m. might not make much of a difference.
• If you live in a rural area. In this instance, lights might help burglars more than deter them by providing light to help them see. And, unlike in an urban area, there are few people around to spot them milling about suspiciously in the glow of that porch light.

An Even Better Option: Automate Your Lights

The goal of lighting, at least from a security standpoint, is to make burglars think someone is home. The most effective way to do that is through lights, both inside and out, that turn on and off at varying times. You can accomplish this through systems that automatically turn lights on after sundown, or even new options that allow you to control lights from your phone or other mobile device.

And, don’t forget motion-sensing lights. They’re affordable, and they can startle burglars and even impair their vision in the moments after they illuminate.

Other Things to Consider

However you use your lights, it might not matter if you don’t take other security measures. For example, are your trees and shrubs trimmed, or do they instead provide cover for someone casing your home? Do you have a good relationship with your neighbors? Will they notice if someone suspicious is outside? Do they even know when you’re going out of town?

Remember, turning on your lights may only be truly effective as part of an overall strategy to keep your home secure.

Reposted with permission from the original author, Safeco Insurance.