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People who search for “live in Indiana work in Illinois taxes” usually share one worry: will both states take a share of my paycheck? It is a fair question. Many households in Northwest Indiana earn a living on the Illinois side of the line, and the paperwork does not always match what neighbors tell you.

This guide gives you the plain answer, the forms that apply (and the ones that do not), a worked example for Porter County and Lake County, and the mistakes we would help you avoid. McMahon & Associates CPAs has served Northwest Indiana from Munster since 1971, so the state line is part of our everyday map.

Quick Summary

If you live in Indiana and work in Illinois, both states can tax your wages because they have no reciprocal tax agreement. Illinois taxes the pay you earn for work done in Illinois at 4.95%. Indiana taxes all your income as a resident at 2.95% for 2026, then gives you a credit for the Illinois tax. Indiana county tax still applies in full.

• No reciprocity: Illinois and Indiana are not on each other’s reciprocal lists, so you generally file in both states.
• Illinois: you file Form IL-1040 with Schedule NR as a nonresident when your Illinois wages create Illinois tax.
• Indiana: you file Form IT-40 as a resident and claim the credit for taxes paid to another state, which usually cancels the Indiana state tax on those wages.
• County tax: the Illinois credit does not reduce Indiana county tax, which depends on the county where you lived on January 1.
• Forms: Form IL-W-5-NR and Form WH-47 are not for you, but Form IL-W-4 and Form WH-4 are.

Quick rule of thumb: you pay Illinois’s higher rate on your Illinois pay, Indiana’s state tax is mostly erased by the credit, and your county tax is the extra bill. Plan for that county tax before April, and check your own facts with a CPA.

Which State Taxes Your Wages When You Live in Indiana and Work in Illinois?

Both states can. Illinois taxes wages earned for work done in Illinois, even if you live elsewhere. Indiana taxes its residents on all income, no matter where it was earned. Because the two states have no reciprocal agreement, you generally file a return in each state, and Indiana gives you a credit for tax you paid to Illinois.

Think of it as two separate questions. The first is where the work happened. The second is where you legally live.

A nonresident return is the return you file in a state where you earned income but do not live. A resident return is the return in the state where you are domiciled, which means the place you live and intend to return to.

Illinois asks the work question. Indiana asks the residence question. Your federal return is separate, and federal tax does not change because of your state mix.

Does Indiana Have a Reciprocal Tax Agreement With Illinois?

No, the two states are not reciprocal. A reciprocal agreement lets commuters pay wage tax only to their home state. Illinois lists Iowa, Kentucky, Michigan and Wisconsin as its partners, and Indiana lists Kentucky, Michigan, Ohio, Pennsylvania and Wisconsin. Neither list includes the other state, so the usual two-state rules apply.

The table puts the two official lists side by side.

You may still see Illinois named as a reciprocal state in an older Indiana regulation and on some websites. Indiana’s 1999 individual income tax booklet explained that Illinois ended its agreement with Indiana on January 1, 1998, and that no new agreement had been reached. The Indiana Department of Revenue’s current bulletin and return instructions list only the five states above.

If someone tells you the two states are reciprocal, ask for a current Department of Revenue source. For a deeper look at choosing a local preparer who handles this every season, see our guide on how to choose a CPA in Northwest Indiana.

Do Form IL-W-5-NR and Form WH-47 Apply to You?

No. Form IL-W-5-NR is Illinois’s statement of nonresidence for residents of Iowa, Kentucky, Michigan and Wisconsin. Form WH-47 is Indiana’s certificate of residence for residents of its five reciprocal states. An Indiana resident working in Illinois should not file IL-W-5-NR, because the form is signed under penalties of perjury and names only those four states.

Many online answers mention these forms because they help commuters from other states. They do nothing for an Indiana and Illinois commuter. These are the forms that do matter:

• Form IL-W-4: you give this to your Illinois employer so it can withhold Illinois tax correctly. Without it, Illinois employers must withhold with no allowances.
• Form WH-4: this Indiana form sets your county of residence or county of principal work for Indiana withholding. Use it with any employer that will withhold Indiana tax.
• Form IL-W-6: a nonresident who works more than 30 working days in Illinois may complete this certificate of days worked, which helps the employer allocate pay when it has no time system.

If your Illinois employer is withholding Illinois tax from your pay, that is normal for you. Illinois requires withholding on pay for Illinois work when the employee lives in a state without a reciprocal agreement.

Do You Have to File an Illinois Nonresident Return?

Usually, yes. You file Form IL-1040 with Schedule NR when your Illinois wages are high enough to create Illinois tax. Illinois says a nonresident must file when Illinois base income on Schedule NR is greater than the Illinois exemption allowance. You also file to claim back Illinois tax withheld in error.

Illinois taxes individuals at a flat 4.95%. The exemption allowance is $2,925 per exemption for tax year 2026 and was $2,850 for 2025. On Schedule NR, Illinois prorates the exemption by the share of your income that Illinois taxes, then multiplies what is left by 4.95%.

Most Illinois wages come with withholding. Your W-2 shows Illinois wages and Illinois tax, and Schedule NR starts from the Illinois wages on that form. If the Illinois wage figure on your W-2 is wrong, Illinois wants a letter from your employer on company letterhead. A letter from you or your preparer is not accepted.

Filing the return matters even when withholding looks right. Without it, you cannot show Indiana how much Illinois tax you actually paid, and that figure drives your Indiana credit.

How Does Indiana Tax Your Illinois Wages, and What Is the Credit?

Indiana taxes you as a resident on all your income, including Illinois wages, at 2.95% for 2026. You then claim a credit for taxes paid to another state on the offset credits schedule of Form IT-40. The credit is the smallest of three amounts, so it usually cancels your Indiana state tax on those wages.

Indiana’s credit worksheet asks for three numbers, and your credit is the lowest one:

1. Tax paid to Illinois on the income Illinois taxed, taken from your Illinois return.
2. Indiana’s rate times that income, using the income that both states taxed.
3. Your Indiana state income tax shown on the Indiana return.

Illinois’s 4.95% rate is higher than Indiana’s 2.95%, so the second or third number is almost always the smallest. That means the credit wipes out your Indiana state tax on the Illinois wages, but it cannot refund the extra Illinois tax. The rate gap stays with Illinois. Indiana’s rate is scheduled to drop to 2.90% in 2027.

Two details save headaches. Indiana wants a copy of the Illinois return you filed, along with a worksheet showing how you figured the credit. Also, the credit is figured on income before any deduction that only one state allows, so do not shrink the base for an Illinois-only deduction.

Do You Owe Indiana County Tax on Wages You Earn in Illinois?

Yes, usually. Indiana’s county income tax is based on the county where you lived on January 1 of the tax year. It applies to your Indiana income, and the credit for Illinois income tax does not reduce it. This is the part of the bill that surprises most commuters.

Indiana does allow a county credit, but only for income tax you paid to a locality in another state. Illinois wages usually carry no city or county income tax, so there is typically no local credit to claim. You figure the tax on Schedule CT-40 and carry it to line 9 of Form IT-40.

Your county of residence is the county where you maintained your primary home on January 1. If you move to a new county in March, your county for that year does not change. On the Indiana return you also list the county where you worked on January 1, and the instructions give Illinois its own code, 94.

The table shows the rates for Northwest Indiana counties and the tax on $60,000 of Indiana taxable income. The rates come from the Indiana Department of Revenue’s Departmental Notice #1, effective October 1, 2026.

The notice marks only counties that changed since January 1, 2026, and none of these six carry that mark. Rates can change each January and October, so confirm the current figure when you file. Our Indiana business personal property tax guide covers a different local tax for business owners.

What Does a Real Example Look Like for a Porter County or Lake County Commuter?

Here is an example household, not a real client. A single person earns $61,000 in wages, all at a Chicago office, and lives in either Porter County or Lake County. The Illinois tax is identical in both cases, the credit erases the Indiana state tax, and the county tax makes the difference.

The example uses round numbers and these assumptions: no dependents, wages only, no pre-tax deductions, the $2,925 Illinois exemption for 2026 and the $1,000 Indiana personal exemption. Real returns include more items.

Two lessons stand out. First, Illinois collected $2,875 while Indiana’s own state tax was $1,770, so the $1,105 difference stays with Illinois. Second, the same job and pay cost $600 more per year in Lake County than in Porter County, only because of where the person lived on January 1.

Illinois likely withheld close to its $2,875 during the year. The county tax probably was not withheld at all, so the example household should expect a balance due to Indiana unless it planned ahead. That is what the withholding section below solves.

What If You Live in Illinois and Work in Indiana?

The same rules run in reverse. Indiana taxes wages earned in Indiana, and Illinois taxes its residents on all income. You file an Indiana nonresident return, Form IT-40PNR, and an Illinois resident return, Form IL-1040, and claim Illinois Schedule CR for the tax you paid to Indiana. Households in Chicago’s South Suburbs with an Indiana job face this version.

Here is how the pieces fit:

• Indiana withholding: an Indiana employer must withhold Indiana state tax from an Illinois resident, since Illinois is not a reciprocal state. Form WH-47 is not for you.
• Indiana county tax: if you live out of state on January 1 but your principal place of work is in an Indiana county, that county’s rate applies for the year. The rate is the same as for a resident.
• The Illinois credit: Schedule CR counts income tax paid to another state and to a county or city, so Indiana state and county tax both count. The credit is limited to the lesser of the tax you paid to Indiana or the Illinois tax on that same income.
• Order of filing: prepare the Indiana return first, because the Illinois credit uses the Indiana tax shown on it.

What is Indiana’s 30-day rule for visitors?

A nonresident employee who works in Indiana 30 days or fewer in a calendar year can be exempt from Indiana income tax on that pay, and the employer may skip withholding. Cross the limit and the pay is taxable from the first day. The rule covers employees only, not self-employment income, and it does not apply to Indiana residents. If you are near the line, count your days carefully with a CPA.

How Does Remote or Hybrid Work Change the Answer?

Taxes follow where you physically do the work. Days you work from home in Indiana are Indiana work days, even if your employer is in Chicago, and Illinois treats pay for work done entirely outside Illinois as not paid in Illinois. Days in the Illinois office are Illinois work days. A hybrid schedule means your pay is split by days.

Indiana’s bulletin says remote work is treated as performed where the work actually occurs, regardless of the employer’s location. Illinois’s employer guide also looks at where services are performed. For an Indiana resident, Indiana taxes everything anyway. The split matters most for how much Illinois tax you owe and how much credit you can claim.

• Keep a day log. A simple calendar showing office days and home days is far stronger than a rebuild at filing time.
• Check your W-2. Illinois wages should reflect only pay for Illinois work. Illinois tax withheld on home days may need a refund claim on your Illinois return, supported by an employer letter.
• Ask payroll how it allocates. Illinois describes a working-day method for people who split time between states, and a day counts as an Illinois day when more of that day’s work was done in Illinois.
• Know the withholding limit. Illinois does not require withholding for a nonresident who worked fewer than 31 days in Illinois, but that is an employer withholding rule, not a promise that your wages escape Illinois tax.

How a mixed schedule is treated depends on the facts, so check your own situation with a CPA before you rely on a home-day split.

How Are Self-Employed Commuters and Contractors Taxed?

No employer withholds, so you carry the work yourself. Illinois taxes business income earned in Illinois, even if you live in Indiana. Indiana taxes all your income as a resident and credits the Illinois tax. Both states expect estimated payments when you will owe more than $1,000 after withholding and credits.

For a nonresident, Illinois taxes business income from a business conducted in Illinois. If the business works both inside and outside Illinois, Schedule NR uses an apportionment worksheet to find the Illinois share. Illinois’s tax on that share is the number you carry to Indiana for the credit.

Be careful if you run an S corporation or partnership. Indiana generally does not give the personal credit for taxes charged at the entity level. A narrow exception covers certain elective pass-through entity taxes that mirror Indiana’s own, so ask before you count on it. For wider changes affecting owners, read our summary of the new tax law impacting Indiana businesses.

Clean books make two-state returns easier. Our accounting and bookkeeping services can help you track which jobs happened in which state.

How Do You Set Up Withholding So You Do Not Owe a Surprise in April?

Start with Illinois, which your employer handles once you file Form IL-W-4. Then look at Indiana county tax, which is often not withheld when your employer is in Illinois. Ask payroll whether it can withhold the Indiana county tax voluntarily. If not, plan quarterly estimated payments to Indiana.

Indiana’s bulletin says an Illinois employer with no business connection to Indiana is not required to withhold Indiana state or county tax, and it suggests voluntary withholding or estimated payments. Follow these steps:

1. Give your Illinois employer a current Form IL-W-4. Review it before December 1 each year.
2. Estimate your county tax. Multiply your Indiana taxable income by your January 1 county rate.
3. Ask about voluntary Indiana withholding. If payroll can do it, file Form WH-4 with the right county.
4. Otherwise make estimated payments. Indiana asks for them if you expect to owe more than $1,000 when you file. Use Form ES-40 or Indiana’s online portal.
5. Check Illinois too. Illinois requires estimated payments when you expect to owe more than $1,000 after withholding and credits.

Both states use the same four quarterly dates for 2026 payments: April 15, June 15, September 15 and January 15. Payroll teams can use our payroll services to handle multi-state setup for employees who live and work on different sides of the line.

Which Returns Should You File, and in What Order?

For most Indiana residents who work in Illinois, plan on three returns: your federal return, an Illinois nonresident return and an Indiana resident return. Prepare the Illinois return before the Indiana return, because the Indiana credit uses your final Illinois figures. Form and line names below come from the latest published booklets, so confirm them for 2026.

1. Collect your W-2 forms and any 1099 forms, plus your Illinois estimated payments if any.
2. Prepare the federal return. Both state returns start from it.
3. Prepare the Illinois return. Complete Form IL-1040 as if you were a full-year resident, then use Schedule NR to find the Illinois portion.
4. Prepare the Indiana return. File Form IT-40, report all income, enter your January 1 county, and complete Schedule CT-40 for county tax.
5. Claim the credit. Complete the credit for taxes paid to other states on the Indiana offset credits schedule and enclose your Illinois return.
6. Pay any balance to each state by the due date, which is generally April 15.

Bring a dated address history and your pay stubs. Our tax preparation checklist lists the other documents to gather, and our record retention guide explains how long to keep them.

What Happens If You Move Between Illinois and Indiana During the Year?

You may be a part-year resident of both states. A part-year resident files Indiana Form IT-40PNR, and Illinois Form IL-1040 with Schedule NR. Indiana county tax is fixed by where you lived and worked on January 1, so a move after that date does not change your county for the year.

Illinois taxes all income you receive while you are a resident, whatever the source. When you are not an Illinois resident, it taxes only income from Illinois sources. Indiana works the same way for its own residency period.

Indiana’s county rule can help or hurt in a move year. A person who neither lived nor had a principal place of work in an Indiana county on January 1 is generally not subject to Indiana county tax that year, even after moving in. The reverse also holds: if you lived in an Indiana county on January 1 and left later, county tax can apply to the part of the year you were an Indiana resident. Because your dates matter so much, review a move with a CPA.

What Mistakes Do Commuters Make Most Often?

The most common mistakes are assuming Indiana and Illinois are reciprocal, skipping the Illinois return, forgetting Indiana county tax, and filing Indiana before Illinois. Most problems come from one wrong assumption or one missing step, and each is easy to avoid once you know about it. Here is the fuller list:

• Assuming reciprocity. Filing Form IL-W-5-NR or WH-47 because a friend in another state did.
• Skipping the Illinois return because tax was already withheld. You still need it to claim the Indiana credit.
• Filing Indiana first and guessing at the credit.
• Using W-2 withholding as the credit. Use the tax shown on the other state’s return, not the amount withheld.
• Forgetting county tax, or using the county where you work instead of the county where you lived on January 1.
• Skipping estimated payments on county tax or self-employment income.
• No day log for a hybrid schedule.
• Using old rates or old web pages. County rates and form lines change.

One more habit helps: compare state income tax paid with your other deductions each year. Our guide to standard vs itemized deduction explains how the choice works, including federal limits on what counts.

When Should You Talk to a CPA About Illinois and Indiana Taxes?

A CPA adds the most value when more than one thing changes in the same year, such as a hybrid schedule, a move, self-employment income or a mismatch in withholding. A simple W-2 commuter with one job can often follow the steps in this guide. Consider help in these cases:

• You work a hybrid schedule and your W-2 may not match your real work days.
• You are self-employed, own part of an S corporation or partnership, or do jobs on both sides of the line.
• You moved between Illinois and Indiana, or married someone who lives in another state.
• Your employer withheld the wrong state, or you got a notice from either state.
• You owe more than expected and want to plan estimated payments.

McMahon & Associates CPAs prepares both Illinois and Indiana returns for individuals and businesses from our office in Munster. Learn more about our tax services, or meet the people behind the work on our team page.

Frequently Asked Questions

Do I pay taxes in Illinois if I live in Indiana?

Yes, on wages for work you do in Illinois. Illinois taxes income earned there at 4.95%, and you file Form IL-1040 with Schedule NR when that income creates Illinois tax. You also report all income to Indiana as a resident, where a credit prevents tax on the same wages twice at the state level.

Does Indiana have reciprocity with Illinois?

No. Indiana’s reciprocal states are Kentucky, Michigan, Ohio, Pennsylvania and Wisconsin. Illinois’s are Iowa, Kentucky, Michigan and Wisconsin. Neither list includes the other state, so commuters between Indiana and Illinois generally file returns in both states and use a credit.

How do I file taxes in two states?

File your federal return first, then the state where you earned the income as a nonresident, then your home state as a resident. For an Indiana resident working in Illinois, that means Illinois Form IL-1040 with Schedule NR, then Indiana Form IT-40 with the credit for taxes paid to another state and a copy of the Illinois return.

Can I claim a credit for Illinois tax on my Indiana return?

Yes. Indiana allows a credit for income tax paid to Illinois on income that both states taxed. The credit is the smallest of the Illinois tax paid, Indiana’s rate times the income taxed by both states, and your Indiana state tax. It does not reduce Indiana county tax.

Who do I file with if I commute to Chicago?

If you live in Indiana, you file with the IRS, with the Illinois Department of Revenue as a nonresident, and with the Indiana Department of Revenue as a resident. Your county of residence on January 1 sets your Indiana county tax. A CPA can prepare all three so the numbers agree.

Why do I owe Indiana tax when Illinois already withheld?

Usually because of county tax. The Illinois credit typically erases your Indiana state tax on those wages, but it does not offset Indiana county tax, and an Illinois employer often does not withhold it. Estimate the county tax early and make estimated payments if needed.

Do I pay Illinois tax on days I work from home in Indiana?

Generally no. Illinois treats pay for work done entirely outside Illinois as not paid in Illinois, and Indiana treats remote work as done where you physically sit. If your employer still withholds Illinois tax on those days, you may need a letter from the employer and a refund claim. Keep a day log.

What if I live in Illinois and work in Indiana?

You file Indiana Form IT-40PNR as a nonresident and Illinois Form IL-1040 as a resident, then claim Illinois Schedule CR for the Indiana state and county tax you paid. Indiana county tax follows the county of your principal work on January 1. Prepare the Indiana return first.

What Is the Next Step?

You can also learn more about our tax services for individuals and business owners.

About the Author

McMahon & Associates CPAs is a locally owned accounting firm at 10010 Calumet Avenue, Munster, Indiana 46321. The firm was established in 1971 and serves Northwest Indiana and Chicago’s South Suburbs. Our team provides accounting and bookkeeping, payroll, tax, consulting, and audit services to businesses and individuals. Call 219.924.3450 or visit our team page to meet the people behind the work.