Illinois Estate Tax Calculator: tax by estate size
2026 law · reviewed September 3, 2026
| Taxable estate | Illinois tax | Illinois, as % of estate | Federal tax, one exclusion | Combined |
|---|---|---|---|---|
| $4,000,000 | $0 | 0.0% | $0 | $0 |
| $4,500,000 | $142,857 | 3.2% | $0 | $142,857 |
| $5,000,000 | $285,714 | 5.7% | $0 | $285,714 |
| $6,000,000 | $456,071 | 7.6% | $0 | $456,071 |
| $7,000,000 | $565,603 | 8.1% | $0 | $565,603 |
| $8,000,000 | $680,634 | 8.5% | $0 | $680,634 |
| $10,000,000 | $926,923 | 9.3% | $0 | $926,923 |
| $12,000,000 | $1,195,517 | 10.0% | $0 | $1,195,517 |
| $15,000,000 | $1,609,310 | 10.7% | $0 | $1,609,310 |
| $20,000,000 | $2,298,965 | 11.5% | $1,080,414 | $3,379,379 |
Illinois and federal estate tax by taxable estate, 2026 law, one all-Illinois estate, no deductions, one federal exclusion.