State guide · Illinois · 2026–27
What grade is my kid in Illinois?
Children must turn 5 on or before September 1.
Calculate for your child
The Illinois rule in detail
| Kindergarten cutoff | Turn 5 by September 1 |
|---|---|
| Who sets it | Set statewide |
| Legal basis | 105 Ill. Comp. Stat. 5/10-20.12 |
| School required from | Age 6 to age 17 |
| Kindergarten mandatory? | No — kindergarten is optional |
How Illinois compares
20 states use the same September 1 cutoff: Alabama, Alaska, California, Connecticut, Florida, Georgia, Idaho, Maryland, Michigan, Minnesota, Mississippi, New Mexico, Oklahoma, Oregon, Rhode Island, South Carolina, South Dakota, Texas, Utah and Wisconsin. 16 have an earlier cutoff and 8 have a later one, so a child born the same day can land a full grade apart depending on where they live.
28 states require school attendance to begin at age 6, Illinois among them. 11 states and DC start compulsory schooling earlier.
Like most of the country, Illinois does not mandate kindergarten — only 17 states and DC do.
School districts in Illinois
See the 855 school districts in Illinois, county by county, with enrollment and each district's website. County directories: Bureau County · Champaign County · Clinton County · Cook County · DuPage County · Grundy County · Jefferson County · Kankakee County · Lake County · LaSalle County · Livingston County · Madison County · Marion County · McHenry County · Ogle County · Peoria County · Sangamon County · St. Clair County · Tazewell County · Vermilion County · Will County · Winnebago County.
Starting early in Illinois
A child on a full-year calendar who turns 5 within 30 days of the start of the school year may be admitted after a readiness assessment.
Early entrance is decided locally even where state law allows it, so ask your district office what evidence they expect and when the window closes.