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
$157
8 hours/day · 2,000–5,000 W
Ductless Mini-Split · per month
$35.80
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 power | 2,000–5,000 W | 400–2,000 W |
| Typical usage | 8 hours/day | 8 hours/day |
| Energy per month | 851 kWh | 195 kWh |
| Cost per month (US avg) | $157 | $35.80 |
| Cost per year (US avg) | $1,880 | $430 |
| Cost per month in Hawaii | $443 | $101 |
Rates as of May 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 (18.4¢/kWh), the ductless mini-split is cheaper: about $35.80/month versus $157/month for the central air conditioner — a difference of $121 per month.
How much could I save per year by choosing the ductless mini-split?
About $1,450 per year at typical usage and average rates. In Hawaii (52¢/kWh) the annual gap grows to roughly $4,097.
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 Idaho at 12.4¢/kWh to Hawaii at 52¢/kWh. Open each appliance's page for the exact cost in your state.