Warren County residents will pay an additional $3.43 million in state income taxes this year, according to an analysis by Local Government Information Services (LGIS).
LGIS combined Illinois Department of Revenue data with a forecast by Senate Democrats to estimate how much additional income tax will be paid in each Illinois zip code.
The following Warren County communities will pay the most: Monmouth ($2,261,443 total/$456 per person), Roseville ($399,641/$557), Kirkwood ($217,955/$530) and Cameron ($198,161/$661).
Retroactive to July 1, the higher rate -- now 4.95 percent, up from 3.75 percent -- will be withheld from employee paychecks over the last six months of 2017.
Before the hike, someone earning $50,000 paid $72 in state income tax per paycheck when paid twice a month. That person will now pay $95, or an additional $600 per year.
Senate Democrats estimate the tax hike will siphon $4.453 billion more this year from individual taxpayers. Businesses will pay another $1 billion.
---
How much more will your community pay?
State income taxes have increased to 4.95 percent from 3.75 percent. This chart shows how much more taxpayers in your community will pay for state government.
| Ranking | Community | Zip | Estimated State Income Tax Increase |
| 1 | Monmouth | 61462 | $2,261,443 |
| 2 | Roseville | 61473 | $399,641 |
| 3 | Kirkwood | 61447 | $217,955 |
| 4 | Cameron | 61423 | $198,161 |
| 5 | Little York | 61453 | $151,321 |
| 6 | Berwick | 61417 | $87,087 |
| 7 | Smithshire | 61478 | $71,620 |
| 8 | Gerlaw | 61435 | $48,639 |
| Total | $3,435,866 |
Top income tax-paying communities in Warren County
This chart shows the ranking of communities by highest income taxes paid in Warren County.
| Ranking | Community | Zip | Average State Income Tax Increase* | Total Returns filed by Zip |
| 1 | Berwick | 61417 | $680 | 128 |
| 2 | Cameron | 61423 | $661 | 300 |
| 3 | Gerlaw | 61435 | $586 | 83 |
| 4 | Roseville | 61473 | $557 | 718 |
| 5 | Kirkwood | 61447 | $530 | 411 |
| 6 | Smithshire | 61478 | $527 | 136 |
| 7 | Little York | 61453 | $522 | 290 |
| 8 | Monmouth | 61462 | $456 | 4,960 |
*Assumes tax increase will meet Senate Democrats' projections.
Alerts Sign-up