LED light bulbs: reading the Lighting Facts label and cost of ownership

Reading the Lighting Facts label

• Brightness: shown in lumens. Look at lumens rather than watts, since LED bulbs use far less power than older bulbs of the same brightness.
• Estimated yearly energy cost: a figure printed on the label, based on assumptions that are stated on the package, such as hours of use per day and an electricity price. Your cost depends on your own use and rates.
• Life: a maker's estimate, shown in hours or years under the stated assumptions.
• Light appearance: shown as color temperature in kelvins, from warm to cool. Warm tones suit living rooms and bedrooms, and cooler tones are often used in kitchens and work areas. It is a matter of taste.
• Energy used: shown in watts.
• Contains mercury: LED bulbs do not usually, but the label has a statement on it if the bulb does.

Fit and compatibility

• Base: bulbs have a screw base or other fittings. Standard household sockets are common, and you should check the base type in your fixture.
• Shape and size: check that the bulb fits inside the fixture or shade.
• Dimmable: if your fixture has a dimmer, check that the bulb is labeled dimmable and compatible with the dimmer type. Mismatches can cause flicker or buzzing.
• Enclosed fixtures: some bulbs are not made for enclosed fixtures. Check the label.
• Smart bulbs: need a compatible hub or app, and they cost more.
• ENERGY STAR: a program from the U.S. EPA and the Department of Energy. A bulb with the mark has met the program's requirements. Look for the mark on the package for any bulb you are considering.

Our angle: total cost of owning a bulb

A cheap bulb that burns out early, or flickers on your dimmer, can cost more than a better one. To compare, add the price of the bulb to the energy cost over the life stated on the label, using the label's yearly energy cost as a guide, or your own electricity rate. Divide by the years of life to get a yearly cost. Multipacks lower the price per bulb. Buy one bulb of an unfamiliar type first, especially for dimmers, and compare the color to what you like. Replace the bulbs you use most first, since the savings add up there.

1. Read the life and the yearly energy cost on the label.
2. Add the bulb price to the energy cost over its life.
3. Divide by the years of life to compare the yearly cost.

Disposal and recycling

• Many places accept used bulbs for recycling, and some stores take them. Check what is near you.
• Compact fluorescent bulbs contain a small amount of mercury and should be recycled and not thrown in the trash. Follow your local rules.
• Handle broken bulbs with care, and follow the local guidance.