Illinois · NOAA station KORD
Heating with a mini-split in Chicago, IL
The short answer
In Chicago, a median ENERGY STAR cold-climate mini-split heating a 24,000 BTU/h design load should cost about $1,197 a year: $548 more than natural gas (90% efficient), and 61% less than electric resistance. The 99% design temperature is 4°F, so capacity at 5°F matters here.
The winter you are actually buying for
This is Chicago's average year of hourly temperatures from 2015 through 2024 (87,636 readings at Chicago O'Hare International Airport, 100% of all hours). The dashed line is the 99% design temperature: only 1% of hours are colder.
What it costs, by fuel
Mini-split modeled as a median certified cold-climate unit sized to cover the load at 4°F. Seasonal efficiency in Chicago's weather: COP 2.54. In 93 hours a year the load exceeds capacity and the estimate adds electric backup.
Three house sizes
| Design load | Heat pump | Gas | Oil | Propane | Resistance | Seasonal COP | Systems that cover it |
|---|---|---|---|---|---|---|---|
| 12,000 BTU/h | $598 | $324 | $734 | $609 | $1,521 | 2.54 | 10,935 of 14,941 |
| 24,000 BTU/h | $1,197 | $649 | $1,468 | $1,217 | $3,042 | 2.54 | 5,303 of 14,941 |
| 36,000 BTU/h | $1,795 | $973 | $2,202 | $1,826 | $4,563 | 2.54 | 2,457 of 14,941 |
The last column counts ENERGY STAR cold-climate systems whose published 5°F and 47°F capacities, joined by a straight line, still reach the design load at Chicago's 4°F. How sizing works.
Not a quote. Real bills depend on insulation, thermostat habits, installation and your own Manual J. Use this to decide whether a heat pump is worth pricing, then get two local quotes.
Questions people ask
Will a mini-split work in Chicago in winter?
Yes, if it is a cold-climate model. Chicago's 99% design temperature from 2015–2024 hourly data is 4°F, and the lowest hour recorded was -23°F. The median ENERGY STAR cold-climate unit keeps 88% of its 47°F heating capacity at 5°F. Hours per year at or below 5°F in Chicago: 93.
Is a heat pump cheaper than natural gas in Chicago?
At a 24,000 BTU/h design load, we estimate $1,197 a year with a median cold-climate mini-split versus $649 for natural gas at 90% efficiency, using 18.91¢/kWh electricity and 2024 Illinois fuel prices. That is $548 more than natural gas.
How big a mini-split do I need in Chicago?
Size to your home's heat loss at 4°F, not to square feet. For a 24,000 BTU/h load, a unit shaped like the median certified system needs about 27,265 BTU/h of 47°F capacity. 5,303 of the 14,941 certified systems cover that load at 4°F.