Most people assume the answer is obvious by now — just buy LED. And for the majority of situations, that instinct is correct. But the “why” behind it matters more than the conclusion, because there are still specific situations where understanding the trade-offs changes the decision. This is a head-to-head comparison built on actual numbers, not marketing copy.

The Three Bulb Types, Quickly Explained

Incandescent: The original electric bulb. Produces light by heating a wire filament to incandescence. The warm, familiar light most people grew up with — but an extremely inefficient converter of electricity to light, with roughly 90% of energy lost as heat.

CFL (Compact Fluorescent Lamp): Uses a gas-discharge tube to produce light and was widely adopted as an energy-saving alternative to incandescent. More efficient, but contains mercury, has a slow warm-up time to full brightness, and has been largely superseded.

LED (Light-Emitting Diode): Passes electrical current through a semiconductor, producing light directly with very little heat. Highly efficient, reaches full brightness instantly, contains no hazardous materials, and lasts dramatically longer than either alternative.

The Full Comparison Table

Every meaningful metric, side by side. Numbers are based on standard 800-lumen output (the rough equivalent of a traditional 60W bulb), running 3 hours per day at the US average electricity rate of $0.16 per kWh.

Energy Use: Where the Real Money Goes

The energy cost difference looks small on a per-bulb basis until you multiply it across a home. The average American household has around 30 light sockets. If those are all incandescent, you’re spending roughly $315 per year just on lighting electricity. Switch to LED and that figure drops to around $42–$52. That’s not a marginal improvement — it’s an 85% reduction in lighting electricity costs.

For a deeper breakdown of how those savings accumulate over months and years — including the payback period calculations that account for the upfront cost of switching — our energy savings analysis does the full math.

10-Year Cost Per Bulb (3 hrs/day · $0.16/kWh)

These numbers explain why incandescent bulbs have largely disappeared from store shelves across Europe and are being phased out in the United States. The economics weren’t close — they were separated by an order of magnitude.

Light Quality: Is LED Light Actually Good?

This is where the conversation gets more nuanced. Incandescent bulbs produce a continuous spectrum of light that renders colors almost perfectly (CRI near 100). LED bulbs don’t produce a continuous spectrum — they produce specific wavelengths, then use phosphor coatings to broaden the output. The result is a CRI that ranges from around 80 in budget bulbs to 98+ in high-quality lighting designed for photography, retail, or medical use.

For most home applications, a CRI of 85–90 is indistinguishable from incandescent to the naked eye. CRI becomes noticeable in specific circumstances: under a bulb with CRI below 80, red tones look muddy and skin tones appear slightly off. This is why bathrooms, makeup mirrors, and retail display lighting benefit from the highest-CRI LED bulbs available.

Color temperature is a separate axis of quality — and one of LED’s genuine advantages. Incandescent bulbs are fixed at around 2700K (warm yellow). CFL bulbs offer a few options but are known for inconsistency. LEDs are available across the full range from 2200K (candlelight warm) to 6500K (overcast daylight). Our color temperature guide explains what each Kelvin value actually looks like in practice.

Lifespan: How Much Does Longevity Actually Matter?

A rated lifespan of 25,000 hours for LED sounds impressive, but what does it mean in practice? At 3 hours of use per day, a 25,000-hour LED bulb lasts approximately 22 years. At 8 hours per day — common in commercial applications — that’s still over 8 years.

Incandescent bulbs at 1,000–2,000 hours would need to be replaced every 1–2 years at the same usage rate. Over a 25-year period, you’d purchase roughly 12–25 incandescent bulbs to replace one LED. Multiplied across a home, the replacement hassle alone — think recessed cans on 12-foot ceilings, chandeliers with 16 bulbs — becomes a practical argument beyond the pure economics.

“After 25 years of use, an LED’s story may not even be over. An incandescent bulb wouldn’t have survived the first year.”

When Incandescent Still Makes Sense

There are a handful of situations where incandescent remains reasonable. Oven bulbs, appliance bulbs rated for high heat, and certain specialty fixtures with unusual base types may still use incandescent because no suitable LED replacement exists or the heat from an incandescent is actively useful — as in some incubator or terrarium setups. Decorative candelabra and chandelier fixtures increasingly have quality LED alternatives, though the visual difference in flame-tip styles is noticeable to some people.

Vintage Edison-style LED filament bulbs have also narrowed the aesthetic gap significantly — they produce the warm, visible-filament look of antique incandescent bulbs while using a fraction of the energy.

When to Consider CFL

Rarely, at this point. If you have existing CFL fixtures already installed and working, replacement-in-kind makes sense to avoid unnecessary waste. But for any new purchase, LED now matches or exceeds CFL on every meaningful metric: energy use, lifespan, instant brightness, dimmability, and lack of mercury. The price premium that once justified CFL has effectively disappeared — LED bulbs cost the same or less than comparable CFLs in most retail outlets today.

The Bottom Line

LED bulbs win on energy efficiency, lifespan, operating cost, color options, dimmability, cold-weather performance, and environmental impact. Incandescent bulbs offer near-perfect color rendering at a low upfront price but are extremely expensive to run over time. CFL bulbs were a transitional technology — better than incandescent but outclassed by LED across the board.

For most people setting up or upgrading their home lighting, the only decision that remains is which LED bulb to choose — not whether to choose LED. That’s where factors like color temperature, CRI, dimmability compatibility, and form factor come in. Our room-by-room LED lighting guide walks through those decisions for every space in a home.

Continue Reading

• How Much Do LED Lights Really Save on Energy Bills? — full payback period calculations and long-term savings by household size
• Understanding LED Color Temperature — what 2700K, 3000K, 4000K, and 5000K actually look like in your home
• LED Lighting for Your Home: Room-by-Room Guide — lumens, color temp, and fixtures for every room in one place