LED vs CFL vs Incandescent Bulb Cost in Illinois
Per bulb, over 10 years at 3 hrs/day and Illinois’s 20.47¢/kWh: an LED costs about $20.43, a CFL costs $35.14, and an incandescent costs $149.49. Switching to LED saves $129.06 per bulb. All three bulbs produce equivalent light (~800 lumens, “60W-equivalent”). Differences are entirely electricity + replacement bulbs. A typical home has about 40 light bulbs. Replacing 40 incandescent bulbs with LEDs in Illinois saves roughly $5162 over 10 years, plus you avoid 360 trips up a ladder. Each bulb is assumed to run 3 hours per day for 10 years. Energy cost = watts × hours × rate. Replacement bulbs use rated lamp life (LED 25,000 hr, CFL 8,000 hr, incandescent 1,200 hr). Prices: LED $2.5, CFL $3.0, incandescent $1.5 — typical 60W-equivalent prices at major U.S. retailers. Illinois’s residential rate of 20.47¢/kWh comes from the U.S. EIA Electric Power Monthly (April 2026). Affiliate links — we may earn a small commission at no cost to you. For bulbs that are on 1+ hour/day, switching pays back within 6–18 months even after throwing the old bulb away. For rarely-used bulbs (closets, attics), wait for the old one to die. Smart LEDs draw about the same energy as regular LEDs (8–10W) but cost 3–6× more up front. They’re a convenience purchase, not an energy purchase. Use the figures above as a baseline. The energy-cost column scales linearly with your actual rate — if your rate is half Illinois’s, halve those numbers. The replacement-bulb column doesn’t change.Bulb Energy use (10 yr) Energy cost Bulb replacements Total 10-yr cost LED (8W, ~25,000 hr life) 87.6 kWh $17.93 1 × $2.50 $20.43 CFL (13W, ~8,000 hr life) 142.3 kWh $29.14 2 × $3.00 $35.14 Incandescent (60W, ~1,200 hr life) 657.0 kWh $134.49 10 × $1.50 $149.49 Whole-house impact in Illinois
How we calculated this
LED bulbs worth buying
FAQ
Are LEDs really worth it if I already have incandescent bulbs at home?
What about smart bulbs?
What if my electricity rate is different?