Chicago, IL 60694 Frost Dates
When can you plant in Chicago, IL?
Typically, the last spring freeze lands around 04/11, roughly 226 days out. The first fall frost typically arrives around 10/31, about 201 frost-free days later.
Chicago sits in USDA Zone 6b (-5 to 0°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
About 9 weeks of growing season left in Chicago before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
The actual range around Chicago's last frost
04/11 is the middle of 30 years of NOAA records, not a promise. Plant by 03/30 and you're betting against frost in roughly 9 years out of 10. 04/27 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Chicago compares
About 201 days separate Chicago's last and first frost, putting it 17,436 of 40,283 ZIP codes nationally. Within IL, it ranks 230 of 1,548.
Learn more
zone vs. frost date covers why Zone 6b and Chicago's frost date answer different questions. the frost range covers how to read the range around Chicago's dates instead of trusting one.