Illinois's rhymes with:
annoys, hanoi's, noise, noyes, aloys, annoys, boies, bolshoi's, boy's, boyes, boys, boys', boyz, croix's, deploys, destroys, eloise, employs, enjoys, hanoi's, joy's, joys, mccoys, moise, moyes, noise, noyes, ploys, poise, roy's, roys, toy's, toys, toys', troise
Illinois's sounds like:
ilana's, illinois, illinois', illness, illnesses