A 3-ton central air conditioner in Arkansas costs about $101.98 in July and $376 a year at 13.74¢/kWh; an 8,000 BTU window unit about $21.28 in July.
At 13.74¢/kWh — Arkansas average, Jan–Aug 2026 (EIA). That is 24% below the U.S. average of 18.19¢.
| Efficiency | Per year | vs yours |
|---|---|---|
| SEER2 13.4 (min · North) | $401 | +$25.25 |
| SEER2 14.3 (min · South) | $376 | — |
| SEER2 15.2 (ENERGY STAR) | $354 | −$22.26 |
| SEER2 17 (ES average) | $316 | −$59.70 |
| Month | Full-load hours | 3-ton central | 8,000 BTU window |
|---|---|---|---|
| February | 1 | $0.43 | $0.09 |
| March | 10 | $3.63 | $0.76 |
| April | 21 | $7.25 | $1.51 |
| May | 94 | $32.43 | $6.77 |
| June | 208 | $72.11 | $15.05 |
| July | 295 | $101.98 | $21.28 |
| August | 271 | $93.87 | $19.59 |
| September | 147 | $50.78 | $10.59 |
| October | 35 | $12.16 | $2.54 |
| November | 2 | $0.85 | $0.18 |
DOE's room-AC test assumes 750 full-load hours a year for a typical U.S. home. We scale it by Arkansas's population-weighted cooling degree days (1,762 ÷ 1,216) and spread it over the months the same way: 1,087 hours a year. Your thermostat setting and insulation move this a lot — switch the calculator to your own hours if you know them.
3 tons = 36,000 BTU/h ÷ SEER2 14.3 = 2,517 W. × 1,087 h = 2,736 kWh × 13.74¢ = $376.
The full method, material data and tips are on the main air conditioner cost calculator page.