Chicago to Nashville has become a well-worn path, and the tax side of it is unusually simple to model: Illinois charges a flat 4.95% regardless of income, and Tennessee charges nothing at all. Here is what that looks like at four salary levels, computed exactly the way our salary calculator does it.
At $75,000
| Illinois | Tennessee | |
|---|---|---|
| Federal tax | $7,670.00 | $7,670.00 |
| State tax | $2,915.55 | $0.00 |
| FICA | $5,737.50 | $5,737.50 |
| Net take-home | $58,676.95 | $61,592.50 |
Tennessee take-home is $2,915.55 higher — about $242.96 more per month.
At $100,000
| Illinois | Tennessee | |
|---|---|---|
| Federal tax | $13,170.00 | $13,170.00 |
| State tax | $4,153.05 | $0.00 |
| FICA | $7,650.00 | $7,650.00 |
| Net take-home | $75,026.95 | $79,180.00 |
Tennessee take-home is $4,153.05 higher — about $346.09 more per month.
At $150,000
| Illinois | Tennessee | |
|---|---|---|
| Federal tax | $24,734.00 | $24,734.00 |
| State tax | $6,628.05 | $0.00 |
| FICA | $11,475.00 | $11,475.00 |
| Net take-home | $107,162.95 | $113,791.00 |
Tennessee take-home is $6,628.05 higher — about $552.34 more per month.
At $250,000
| Illinois | Tennessee | |
|---|---|---|
| Federal tax | $51,304.00 | $51,304.00 |
| State tax | $11,578.05 | $0.00 |
| FICA | $15,514.00 | $15,514.00 |
| Net take-home | $171,603.95 | $183,182.00 |
Tennessee take-home is $11,578.05 higher — about $964.84 more per month.
The pattern worth noticing
Because Illinois is flat rather than progressive, the gap grows in a straight line with taxable income rather than accelerating. That makes this pair predictable in a way the California and New York comparisons are not — roughly 4.95 cents of every additional taxable dollar, at any salary. At $75,000 the difference is about $242.96 a month; at $250,000 it is $964.84 a month.
What this comparison doesn’t include
State income tax is one line in a much larger budget. Housing costs, sales tax, property tax rates, and general cost of living all move independently of income tax and can comfortably outweigh it in either direction — a smaller state tax bill does not automatically mean more money left at the end of the month once rent or a mortgage is paid. This comparison isolates income tax because that is the part with a precise, calculable answer.
A note on precision: these figures apply each state’s bracket schedule to your federal taxable income. Tennessee levies no personal income tax on wages, so its column is federal tax and FICA only. Illinois’s figure comes from its own published brackets. States also have their own credits, exemptions and deductions that this model does not carry, so treat the numbers as a close estimate of the gap rather than a filled-in tax return. The methodology page sets out exactly what is and is not modelled.
Run your own numbers
Every figure above assumes a single filer taking the standard federal deduction and nothing else. Your own result will move with filing status, deductions, and your actual salary — put your real number into the salary calculator for Illinois, Tennessee, or any other state, and you can share or bookmark the result straight from the page.