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Central Air Conditioner vs Ductless Mini-Split: Which Costs Less to Run?

Ducted central AC versus ductless mini-splits is both a comfort and an efficiency decision — and duct losses are the hidden variable.

Central Air Conditioner · per month

$160

8 hours/day · 2,000–5,000 W

Ductless Mini-Split · per month

$36.58

8 hours/day · 400–2,000 W

Verdict

Mini-splits generally win on cost: no duct losses (which waste 20–30% in typical attics), inverter compressors that sip at part load, and per-room zoning. Central wins on whole-house evenness and existing infrastructure. For additions, bonus rooms, or replacing window units, the mini-split is the efficiency choice.

Side by side

Central Air Conditioner Ductless Mini-Split
Typical power2,000–5,000 W400–2,000 W
Typical usage8 hours/day8 hours/day
Energy per month851 kWh195 kWh
Cost per month (US avg)$160$36.58
Cost per year (US avg)$1,921$439
Cost per month in Hawaii$397$90.66

Rates as of April 2026. Adjust the assumptions on each appliance's page: Central Air Conditioner · Ductless Mini-Split.

Frequently asked questions

Which is cheaper to run: a central air conditioner or a ductless mini-split?

At typical usage and the current U.S. average rate (18.8¢/kWh), the ductless mini-split is cheaper: about $36.58/month versus $160/month for the central air conditioner — a difference of $123 per month.

How much could I save per year by choosing the ductless mini-split?

About $1,481 per year at typical usage and average rates. In Hawaii (46.6¢/kWh) the annual gap grows to roughly $3,672.

Do these numbers apply to my state?

The ratio between the two stays the same everywhere, but the dollar gap scales with your rate — from North Dakota at 12.4¢/kWh to Hawaii at 46.6¢/kWh. Open each appliance's page for the exact cost in your state.