Most of WILL-FM's schedule is classical music with NPR news programs heard in weekday morning and afternoon drive times.

It broadcasts with a grandfathered Effective Radiated Power (ERP) of 105,000 watts, more than double of what would be permitted today in Illinois.

At that time, the station and subchannel adopted a format branded as "Illinois Soul", consisting of a hybrid mix of smooth jazz, neo soul, R&B, and classic hip-hop music, along with African-American hosted NPR programs such as Code Switch and It's Been a Minute and shows hosted by Will Downing and Robert Glasper.

However, the university's existing AM band station, WILL, was restricted to daytime-only operation, so the addition of an FM signal allowed for the expansion of the broadcast service to include nighttime hours.

[9] Following a series of test transmissions, WIUC began regular operations on November 22, 1942, initially with a schedule of 4 to 5:30 p.m. on Monday afternoons.

[12][13] In July 1946 the FCC further directed that FM stations currently operating on 42-44 MHz would have to move to new frequencies by the end of the year,[14] and WIUC was reassigned from 42.9 to 44.7 MHz, although the university reported that the station was suspending operations until it was ready to broadcast on its "high band" frequency.

[18] WILL-FM was among the stations that helped to create NPR, and was one of the ninety that carried the premiere broadcast of All Things Considered in 1971.