If spiral CFLs still glow in your lamps and ceiling fixtures, the question is not which bulb to buy. CFLs have largely left US store shelves, so you are deciding whether to pull working ones now or let them burn out first.
LEDs win on every cost measure, but retiring a working CFL early only pays back quickly in sockets that run several hours a day. Replace high-use, enclosed, dimmed and frequently switched CFLs now.
Let the rest run out, then recycle them.
Incandescent, CFL and LED Over 25,000 Hours of Use
The comparison below uses a 60-watt incandescent as the baseline, about 800 lumens, electricity at $0.15 per kWh, and 25,000 hours of use. That is roughly 23 years at three hours a day.
| Spec | Incandescent (60 W) | CFL (13-15 W) | LED (8-10 W) |
|---|---|---|---|
| Light output | About 800 lumens | About 800 lumens | About 800 lumens |
| Rated lifespan | About 1,000 hours | 6,000-15,000 hours | 15,000-25,000+ hours |
| Bulbs needed for 25,000 hours | 25 | 2-4 (3 at 10,000 hours) | 1 |
| Mercury | None | About 4 mg | None |
| Enclosed fixtures | Yes, within the fixture’s wattage limit | Heat shortens life; check the label | Only if labeled enclosed-fixture rated |
| Full brightness | Instant | 30 seconds to a few minutes | Instant |
| Electricity cost, 25,000 hours | $225.00 | $48.75 (13 W) | $33.75 (9 W) |
| Total cost with bulbs | About $250 at $1 per bulb | About $61 at $4 per bulb | About $37 at $3 per bulb |
Over one socket’s life, the LED saves about $24 against a CFL and more than $210 against an incandescent. Most of that gap is electricity, not the price of the bulb.
The EPA notes that CFLs hold a small amount of mercury, about 4 milligrams on average, and release none while intact. The risk arises only when one breaks or lands in the trash.
A cooperative extension comparison of LED, CFL and incandescent bulbs shows the same ranking on wattage, lifespan and heat output. LEDs also send far less heat into the room than incandescents.
When Retiring a Working CFL Pays Off
A 9-watt LED replacing a 13-watt CFL saves 4 watts. Whether that justifies removing a bulb that still works depends almost entirely on how many hours a day the socket runs.
| Daily use | Hours per year | Yearly savings vs. 13 W CFL | Payback on a $3 LED |
|---|---|---|---|
| 1 hour | 365 | $0.22 | About 14 years |
| 3 hours | 1,095 | $0.66 | About 4.5 years |
| 6 hours | 2,190 | $1.31 | About 2.3 years |
| 10 hours | 3,650 | $2.19 | About 1.4 years |
Figures assume $0.15 per kWh. Check your bill: at $0.30 per kWh every payback time halves, and swapping a 15-watt CFL shortens it further.
Swap these CFLs now
- Long-running fixtures: kitchen ceiling lights, living room lamps and porch lights on five or more hours a day.
- Frequently switched spots: bathrooms, hallways and closets, where constant on-off cycling shortens CFL life and the warm-up delay is most annoying.
- Dimmer circuits: most CFLs flicker, buzz or fail early on dimmers.
- Cold or enclosed fixtures: CFLs start dim in cold garages and outdoors, and trapped heat wears out their electronics.
- Kids’ rooms and tippable lamps: a broken CFL means glass plus a mercury cleanup.
Let these burn out
- Guest rooms, storage closets, basement storage areas and attics.
- Any socket used less than an hour a day, where payback runs past a decade.
Take a two-bedroom apartment with 14 CFLs. Swapping the five that run about six hours a day costs $15 and saves about $6.50 a year, paying back in roughly 2.3 years.
The other nine can stay until they fail.
Lighting is one of the cheaper fixes; for bigger wins, see our guide to changes that cut energy bills and pay for themselves.
Matching the LED to the Socket You Are Changing
- Brightness: 450 lumens replaces a 40 W incandescent, 1,100 replaces 75 W and 1,600 replaces 100 W.
- Color temperature: 2700K matches most CFL “soft white” bulbs. Choose 3000K for crisper warm light, 3500-4100K for kitchens and work areas, and 5000K only for garages and workshops.
- Base: most lamps use E26 medium bases; chandeliers often use E12 candelabra; track and recessed spots may use GU10 pins.
- Dimmable: on a dimmer circuit, buy bulbs labeled dimmable.
Closed globes, sealed outdoor fixtures and some fan light kits need an enclosed-rated LED. LEDs shed heat through a heat sink in the base and dim gradually over their life, so trapped heat makes the electronics fail years early.
When mixing bulbs in one room, keep the color temperature consistent; our guide to layered lighting for warm rooms covers which lamps get which bulbs.
Before changing any bulb, turn off the switch and let the old bulb cool for a few minutes. Use a stable step stool or ladder, never a chair, and hold CFLs by the plastic base rather than the glass spiral.
Recycling the CFLs You Retire
Working or burned-out CFLs should not go in household trash. The EPA’s guidance on recycling and disposal of mercury-containing bulbs points to household hazardous waste sites and retailer take-back programs, and some states forbid trash disposal outright.
Until drop-off day, keep removed CFLs in their original box or wrapped in newspaper in a sturdy container, away from where kids play.
If a CFL Breaks During the Swap
Follow the EPA’s steps for cleaning up a broken CFL. In short:
- Get people and pets out of the room. Open a window or outside door and air the room for 5-10 minutes.
- Turn off central heating or air conditioning so the system does not circulate vapor, and keep it off for several hours if you can.
- Scoop glass and powder with stiff paper or cardboard. Pick up small pieces with sticky tape, then wipe the area with a damp paper towel.
- Do not vacuum the debris; vacuuming spreads mercury vapor and dust.
- Seal everything in a glass jar with a metal lid or a sealable plastic bag, set it outdoors, and follow local disposal rules.
Fixing Flicker and Early LED Failures
Flicker on a dimmer usually means the old dimmer was built for incandescent loads and cannot control a 9-watt LED. An LED-rated dimmer usually solves it.
Replacing a dimmer is wiring work. Shut off the breaker and confirm the circuit is dead with a non-contact voltage tester, or hire a licensed electrician.
An LED that dies within a year in a closed globe almost always overheated; replace it with an enclosed-rated bulb.
Call a licensed electrician if several bulbs flicker in one fixture, bulbs fail repeatedly, or you notice buzzing, warmth or scorch marks at a switch or socket.
Once every socket is LED, add a quick fixture check to your monthly home maintenance calendar. If you want lights to switch off on their own, smart plugs and occupancy sensors trim the hours that drive every figure above.
