Illinois to Florida: Severing Business and Property Ties, Not Just an Address

Most people leaving a high-tax state arrive with a day count in their head. New York has 184. Minnesota has its own version. The number is wrong as a complete answer everywhere, but at least it exists. In Illinois it does not exist at all, and that absence changes what the work of leaving actually is.

35 ILCS 5/1501(a)(20)(A) defines an individual resident two ways and only two ways. You are a resident if you are in Illinois for other than a temporary or transitory purpose during the taxable year. You are also a resident if you are domiciled in Illinois but absent from the state for a temporary or transitory purpose. There is no third route, no permanent place of abode prong, and no threshold of days that flips your status when you cross it. The Department of Revenue regulation at 86 Ill. Adm. Code 100.3020 fills in the definitions and adds examples, and it too declines to give a number.

What the regulation gives instead is two rebuttable presumptions, at 100.3020(f), under a preamble stating that they are not conclusive and may be overcome by clear and convincing evidence to the contrary. The first: an individual receiving a homestead exemption for Illinois property is presumed to be a resident of Illinois. The second: an individual who is an Illinois resident in one year is presumed to be a resident in the following year if present in Illinois more days than in any other state. Note what both presumptions are built out of. One is a property tax filing. The other is a relative comparison rather than an absolute count. Neither is something you clear by staying under a line.

That is the shape of this corridor. Our Illinois residency guide rates the state 3 out of 5 on exit stickiness and 3 out of 5 on audit aggressiveness, below New York and California but firmly in the middle of the pack, and the Department is described by practitioners as opening residency inquiries around a specific triggering event rather than running broad sweeps. Our Florida residency guide rates Florida 1 and 1, because Florida has no personal income tax and audits nobody for leaving. The income tax delta is a flat 4.95 percent against zero, which is real but smaller than the numbers driving the coastal corridors. The delta that surprises people is elsewhere, and it lives in property and in an estate. This article is informational and is not legal or tax advice; work through your own facts with a qualified CPA or tax attorney.

The Illinois case anyone moving from Illinois to Florida should read is Cain v. Hamer, 2012 IL App (1st) 112833, 975 N.E.2d 321. It is usually cited for a single striking fact, which is that taxpayers who spent more Illinois days than Florida days on average still won. That is true and it is not the useful part.

Mr. Cain was a retired self-employed trader from the Chicago Board Options Exchange. The Cains had worked and lived in Illinois since 1964. He retired in 1990 and they built a home in Florida. In early 1995 they bought an Illinois lot intending to build something smaller, abandoned that plan in August, and instead started an addition to their longtime Illinois home. In November 1995 they filed a Florida declaration of domicile renouncing Illinois residency. What was at stake across tax years 1996 through 2004 was roughly 1.9 million dollars in Illinois income tax and penalties.

The court sorted the facts into three piles. Favoring Florida: the Florida home, the declaration of domicile, Florida driver licenses and permanent resident identification cards, Florida voter registration and Florida jury duty summonses, a Florida firearm license, Florida cell phone numbers, a newspaper delivered to the Florida house, credit card data showing 73 percent of expenditures and 61 percent of transactions outside Illinois, and charitable giving that shifted toward Florida as the years went on. Favoring Illinois: they used Illinois income tax preparers exclusively, made political contributions to Illinois candidates and none to Florida candidates, and Mrs. Cain kept renewing an Illinois interior designer license without ever indicating on the renewal forms that she had moved, though she used the license in neither state. Favoring neither: doctors and legal advisors in both states, board and committee seats in organizations in both states, and club memberships in both, at 236,000 dollars of Illinois spending against 422,000 dollars in Florida.

The day count landed in that third pile. Over 1996 through 2004 the Cains spent 1,700 days in Florida, 1,666 in Illinois, and 284 elsewhere. An Illinois average above 183 days a year, and the court treated it as indeterminate rather than dispositive, because Illinois has no threshold for it to cross.

The analysis then ran on two questions. First, did the Cains change domicile. The regulation at 100.3020(d) supplies a two-part test: an Illinois domiciliary loses that domicile by locating elsewhere with the intention of establishing the new location as a domicile, and by abandoning any intention of returning to Illinois. The court instead used the more detailed four-part common law test from Viking Dodge Inc. v. Hoffman, 497 N.E.2d 1346 (Ill. App. Ct. 1986): physical abandonment of the old domicile, intent not to return, physical presence in the new domicile, and intent to make it the new domicile. Because the Cains split their time roughly equally, the court found the first two factors indeterminate and decided the question on the last two, which the Florida voter registrations, the Florida taxes paid, the residency cards and licenses and the declaration of domicile answered. That reasoning drew criticism in the academic literature, because Viking Dodge had put the burden on the taxpayer to establish all four factors.

Second, were the frequent returns to Illinois temporary or transitory in purpose. Here the court held that splitting time evenly does not automatically make presence non-temporary, and that a nexus analysis is useful precisely when the timing analysis is indeterminate. The Cains had the stronger Florida nexus: more spent on Florida clubs, Florida licenses and residency cards, Florida voting, a Florida phone number, distance from Illinois companies, charitable focus shifted to Florida, more money spent in Florida, and burial plots purchased in Florida. They were held to be Florida residents.

Read the winning column again and notice how little of it is about where they slept. It is a list of relationships relocated: the phone, the clubs, the charities, the ballot, the companies, the grave. The one column that hurt them was also relational, and unglamorous: the Illinois tax preparer, the Illinois political giving, a professional license renewed year after year with a stale address. That is the whole lesson of this corridor. Illinois does not ask how many days. It asks whose state you belong to, and it reads the answer off the ties you kept.

Of everything Illinois can hold against a departing resident, the General Homestead Exemption is the cheapest to fix and the most commonly missed, because it is the one tie that continues without anyone doing anything.

The exemption itself is modest. Under 35 ILCS 200/15-175, for taxable years 2023 and thereafter the maximum reduction in equalized assessed value is 10,000 dollars in counties with 3,000,000 or more inhabitants, meaning Cook, and 6,000 dollars in all other counties. It requires the property to be occupied by its owner or owners as their principal dwelling place, and it requires the claimant to have an ownership interest and to be liable for paying the property taxes.

The tax saving is small. The evidentiary cost is not. 86 Ill. Adm. Code 100.3020(f)(1) turns receipt of that exemption into a presumption that you are an Illinois resident, and the preamble to subsection (f) says the presumptions may be overcome by clear and convincing evidence to the contrary. That is a real standard, not a shrug. You are volunteering, to a county government, an annual assertion that an Illinois property is your principal dwelling place, and the state has written a rule that reads it back to you as residency.

The mechanism that makes this dangerous is administrative rather than legal. The exemption is a creature of state law but the counties implement it: 35 ILCS 200/15-175(i) provides that in all counties the assessor or chief county assessment officer may determine eligibility and the amount of the exemption by application, visual inspection, questionnaire or other reasonable methods. In many counties, as an Illinois Department of Revenue administrative law judge put it while citing Professor Ronald Domsky, the exemption renews automatically until the homeowner removes it or the property is sold. Domsky calls it a trap for the unwary in residency disputes, and the phrase is exact. Nobody sends you a form to sign. The presumption reattaches every year on its own.

The Department does use it. Administrative hearing decision IT 24-02, issued April 2, 2024, is worth reading for the texture even though the taxpayers won. The Department issued a Notice of Deficiency for tax year 2013 based on an Illinois street address appearing on the taxpayers’ 2013 federal return combined with the absence of an Illinois return for that year, information it got from the IRS. At the hearing it also pointed to a homestead exemption claimed against the 2013 property taxes, invoking the 100.3020(f)(1) presumption. The administrative law judge found the presumption rebutted, in part because the home was still in the taxpayer’s late mother’s name and her exemption had simply carried over after her death in 2011.

The timeline in that case is the part to sit with. Tax year 2013. Notice of Deficiency dated June 24, 2019. Evidentiary hearing December 21, 2022. Recommendation April 2, 2024. Eleven years from the year in question to the decision, and the whole thing opened on two data points that cost the Department nothing to obtain: an address on a federal return, and a missing state return.

In Cook County the exemption is not only an evidence problem. 35 ILCS 200/9-275 applies to counties with 3,000,000 or more inhabitants and gives the chief county assessment officer machinery to recover erroneous homestead exemptions, defined as an exemption granted for property that was not eligible for it in that taxable year. The lookback runs 3 collection years for one or two erroneous exemptions and 6 collection years where three or more were received, with 10 percent interest per annum from the date the erroneous exemption principal amount would have become due, plus a penalty of 50 percent of the principal amount in the three-or-more case. The process moves through a notice of discovery and then a notice of intent to record a lien, with 30 days to pay before the lien is recorded against the property. There is a way out: a taxpayer who notifies the chief county assessment officer within 60 days after receiving an assessment notice and pays the principal plus interest is not liable for the penalties.

So the arithmetic on a Cook County house is not a 10,000 dollar assessment reduction. It is up to six years of recapture, at 10 percent annual interest, potentially with a 50 percent penalty and a lien, sitting on top of a state-law presumption that you were an Illinois resident the whole time. File the removal with the county when you move, and keep the confirmation.

For a long time the standard advice for an Illinois business owner planning a move was clean. Sell Illinois real estate and Illinois taxes the gain. Sell an interest in the company and, if you were a nonresident by then, the gain was intangible income sourced to your new domicile. Move first, sell second.

Public Act 104-0006 changed that. For tax years ending on or after June 16, 2025, 35 ILCS 5/303(b)(4) allocates to Illinois the gains and losses of a person other than a resident from the sale or exchange of shares in a Subchapter S corporation or of an interest in a partnership, other than an investment partnership, where the pass-through entity is itself taxable in Illinois. The allocation is not all-or-nothing. The gain is allocated in proportion to the average of the entity’s Illinois apportionment factor in the year of the sale or exchange and the two tax years immediately preceding it. If an average of 75 percent of the entity’s income was apportioned to Illinois across those three years, 75 percent of the gain is Illinois income to a nonresident seller.

Read the three-year average as what it is: a lookback that starts running before you decide to sell. The apportionment factors for the two years before a sale are already fixed by the time an owner sits down with a banker. Moving your own domicile in the year of the sale does nothing to them. Illinois deliberately built a rule whose inputs cannot be changed by the seller’s move date, which is the opposite of how the pre-2025 planning worked.

The Department flagged this in Informational Bulletin FY 2025-29 alongside the rest of the act, which also adopted the Finnigan method for apportionment factors and capped the GILTI dividend deduction at 50 percent for corporations, both effective for tax years ending on or after December 31, 2025. The bulletin is titled for legislative changes that may increase current tax year liabilities, and it discusses estimated payment adjustments, which is a fair signal of who it was expected to hit.

The investment partnership carve-out matters and is narrower than it sounds. It reaches investment partnerships as Illinois defines them, not operating businesses that happen to hold investments. An operating S corporation or an operating partnership doing business in Illinois is squarely inside the rule. If you are modeling a business sale against a move, the residency savings and exposure calculator will show you the income tax delta between the two states, but the delta is only half the question here. The other half is what share of the gain Illinois can reach regardless of which state you are living in when the wire clears, and that share was decided by your apportionment factors in years you have already filed.

Suppose you do not sell. You keep the S corporation, or the LLC, or the board seat, or the officer role, and you run it from Naples. Illinois keeps a relationship with you, and each part of it generates a dated record with your name on it.

Start with the entity. Illinois partnerships and S corporations are subject to the personal property replacement income tax at a rate of 1.5 percent on income taxable to Illinois. That obligation belongs to the entity and is unaffected by where its owners live. The entity keeps filing Form IL-1065 or IL-1120-ST every year you hold the interest.

Then the withholding. Pass-through entities that have not elected to pay the pass-through entity tax must make a pass-through withholding payment on behalf of any nonresident member, reported and paid by the entity for the nonresident partner, shareholder or beneficiary. The moment you become a Florida resident, you become a nonresident member, and the entity starts withholding for you. The amounts flow through Schedule K-1-P for partners and shareholders and Schedule K-1-T for beneficiaries, with the calculations on the corresponding K-1-P(3) and K-1-T(3). There is an opt-out, Form IL-1000-E, the Certificate of Exemption for Pass-through Withholding, in which the member certifies that it will file all Illinois income tax returns and make timely payment of all Illinois income taxes due. Note what signing that certificate is: an undertaking to the Illinois Department of Revenue to keep filing Illinois returns.

Or the entity elects the PTE tax. For tax years ending on or after December 31, 2021, a partnership or S corporation may elect on Form IL-1065 or IL-1120-ST to pay tax equal to 4.95 percent of its net income, and each owner takes a credit against their own Illinois tax equal to 4.95 percent times their distributive share of the electing entity’s net income. The election is annual, made by the entity, and it changes who writes the check without changing the fact that Illinois income keeps being allocated to you.

None of this makes you an Illinois resident. All of it makes you an Illinois filer, year after year, in a state where the residency test asks whether your presence and your ties are temporary or transitory. The Cains lost points for using Illinois tax preparers and giving to Illinois candidates. An active officer role in an Illinois operating company is a considerably heavier fact than either, and it is the fact people most often decide to keep.

The commonly missed corollary is the one from our Illinois dossier: continuing Illinois business involvement, whether board seats, LLC management or S corporation officer duties, keeps generating Illinois-source income after the move. Being a nonresident does not end the filing. It changes which form you file.

A nonresident with Illinois-source income files Form IL-1040 with Schedule NR, which determines the income Illinois taxes and computes the tax. The Illinois-source list on that schedule is the durable part of what you keep: Illinois wages from the Illinois copy of a W-2, income from a business conducted in Illinois or the Illinois portion of a multistate business under the apportionment worksheet, income from Illinois partnerships and S corporations as reported on Schedule K-1-P or K-1-T, capital gains or losses from the sale of real property or tangible personal property located in Illinois at the time of the sale, rental income from Illinois property, Illinois farm income, Illinois unemployment compensation, and Illinois lottery and gambling winnings. A part-year resident files the same pair, taxed on everything while an Illinois resident and on Illinois-source income for the rest of the year.

Unlike New Jersey, Illinois runs no nonresident withholding gate at a real estate closing. There is no state form standing between your deed and the county recorder. That is easier and it is also quieter: nothing in the transaction forces you to state your residency on the record, and nothing prompts you to reconcile the sale with the return you intend to file.

The larger number is at the end. Illinois has an estate tax with an exclusion of 4,000,000 dollars, and the exclusion is a taxable threshold rather than a credit against tax. It is not indexed for inflation and it is not portable between spouses. If a gross estate exceeds 4,000,000 dollars after inclusion of adjusted taxable gifts, an Illinois Form 700 must be filed whether or not the IRS requires a federal return.

Here is the part that matters for anyone keeping the Illinois house. The Attorney General’s instructions treat resident and nonresident decedents through the same calculation: for both, a preliminary tax amount is computed assuming all assets are located within Illinois, and the apportioned tax is then determined by multiplying that figure by the ratio of Illinois assets to total assets. Estates with less than 100 percent of their assets in Illinois complete the Form 700 Addendum. Becoming a Florida resident removes the intangibles from the Illinois side of that ratio. It does not remove the Illinois real estate. The lake house is still Illinois property in an Illinois calculation, run against a 4,000,000 dollar threshold that has not moved in years.

Which produces the counterintuitive shape of this corridor for retirees. Illinois is one of the most retirement-friendly states in the country on income tax: Social Security, qualified pension income, and qualifying distributions from 401(k), 403(b), 457(b), traditional and Roth accounts are exempt with no age requirement and no income cap. A retiree living on that income pays Illinois roughly nothing on it today, so the income tax saving from moving to Florida can be close to zero. The savings are in the other two columns. Illinois has the highest statewide effective property tax rate in the country, around 1.92 percent of home value, and an estate tax that starts at 4,000,000 dollars against no Florida estate tax at all. Keeping the Illinois house preserves exactly the two exposures the move was supposed to solve.

Illinois asks for very little in the transition year, and Florida hands you a great deal. Both facts are about evidence rather than tax.

On the Illinois side it is one filing: Form IL-1040 with Schedule NR, which allocates income between the Illinois-resident portion of the year and the nonresident portion. That return states a move date by implication. It should agree with everything else you filed that year, which in practice means the county homestead removal, the last Illinois vehicle registration, and any Illinois professional license renewal. Mrs. Cain’s interior designer license is the cautionary example: a renewal form completed after a declaration of domicile, never updated to show the move, held against her in litigation years later for a credential she used in neither state.

On the Florida side, the destination gives you dated third-party documents that Illinois will never issue. The Declaration of Domicile under Fla. Stat. section 222.17 is a sworn one-page statement, notarized and recorded with the Clerk of the Circuit Court for roughly a ten dollar fee, naming your prior domicile, your Florida county, and the date Florida became your home. The Cains filed one in November 1995 and the court listed it among the facts favoring Florida. No state treats it as conclusive. Its value is that its entire function is to fix a date, under oath, in a record held by someone other than you.

The Florida homestead exemption does more work than its dollar value suggests. It reduces assessed value by up to 50,000 dollars, the first 25,000 applying to all taxing authorities including schools and the second 25,000 applying to value between 50,000 and 75,000 while excluding school levies. What makes it evidence is the application: ownership and occupancy as of January 1, a March 1 filing deadline for that year, and proof of permanent residency in the form of a Florida driver license, voter registration and vehicle registration all showing the homestead address, plus proof that you are not claiming a residency-based tax benefit in another state. County property appraisers cross-check it.

That last requirement closes the loop with Illinois cleanly. Two homestead exemptions, one in each state, are not merely inconsistent in the abstract. The Florida application asks you to certify you are not claiming the Illinois one, and the Illinois one creates a presumption of Illinois residency that must be rebutted by clear and convincing evidence. For any given benefit year you should hold one of them and be able to say which, and the answer should match the move date on your IL-1040 and Schedule NR.

The rest of the Florida checklist is ordinary and the deadlines are the point, because the dates are the evidence. A Florida driver license is required within 30 days of establishing residency. Vehicle registration is required within 10 days. Voter registration has no deadline of its own but must be completed at least 29 days before an election to vote in it. A license obtained in the first month says something a license obtained two years later does not.

Set this corridor next to moving from Illinois to Texas and the origin-state analysis is identical, because the origin state is the same. Illinois asks the same two-prong question, applies the same two presumptions, and reaches the same Illinois-source items on Schedule NR whichever no-income-tax state you land in. What differs is the destination’s paperwork. Texas has no equivalent of the Fla. Stat. 222.17 declaration of domicile, and its homestead exemption operates on its own terms. If the evidence you are trying to build is a dated record of arrival held by a third party, Florida is the more generous destination, and that is a genuine reason to prefer it that has nothing to do with tax rates, since both destinations tax individual income at zero.

Set it next to moving from New York to Florida and the difference is structural. New York gives you a statutory residency test with a permanent place of abode and a day threshold, which means a New York move has a number you can be measured against and a rule you can fail on arithmetic alone. Illinois gives you neither. That sounds like an advantage and it is closer to a trade. New York exposure can be sized. Illinois exposure is a judgment about the totality of your ties, decided years later by someone reading a list of what you kept.

Which is why the operative distinction in this corridor is the one in the title. Changing your address changes almost nothing here. What moves the analysis is the homestead exemption you removed, the Illinois company you sold or did not, the board seat you resigned, the professional license you updated, the preparer you changed, and the house you kept or let go.

The Mobility Map records days and nights by state as they happen. In a state with no day threshold, that matters differently than elsewhere: the count is not a line to clear, it is the input to the more-days-than-any-other-state presumption and the raw material for the nexus comparison a court runs when the timing is indeterminate, exactly as it did in Cain.

Evidence Vault holds what this corridor actually asks for: the county confirmation that the Illinois homestead exemption was removed and the date it was removed, the IL-1040 and Schedule NR for the year of the move, the Florida declaration of domicile with its recording date, the Florida homestead application, the license and vehicle registration with their dates, the Schedule K-1-P forms and any IL-1000-E you signed, and the resignations and transfers that ended Illinois business roles. AuditIQ surfaces retained Illinois ties that keep generating dated records in a state whose assessment window runs three years from the later of the due date or the filing date, six years where 25 percent or more of income was omitted, and has no limit at all on a year for which no return was ever filed. Advisor sharing lets a CPA or tax attorney review the presence record, the transition-year filings and the Illinois-source items together, since only the first of those responds to the move.

ResidencyIQ organizes records and highlights potential exposure factors. It is not a law firm or an accounting firm and does not provide legal or tax advice; work with a qualified CPA or tax attorney on your own domicile, filings, and state exposure.

The two-prong definition of an Illinois individual resident, a person in the state for other than a temporary or transitory purpose during the taxable year or domiciled in the state but absent for a temporary or transitory purpose, is 35 ILCS 5/1501(a)(20)(A): https://www.ilga.gov/Documents/legislation/ilcs/documents/003500050K1501.htm. The Department of Revenue regulation defining resident, domicile, temporary or transitory purpose, the two-part test for losing an Illinois domicile at subsection (d), and the rebuttable presumptions at subsection (f) is 86 Ill. Adm. Code 100.3020: https://www.law.cornell.edu/regulations/illinois/Ill-Admin-Code-tit-86-SS-100.3020. The subsection (f) preamble language that the presumptions are not conclusive and may be overcome by clear and convincing evidence to the contrary, and the text of the homestead exemption presumption at (f)(1), are quoted in Illinois Department of Revenue administrative hearing decision IT 24-02.

Cain v. Hamer, 2012 IL App (1st) 112833, 975 N.E.2d 321, is the source of the case narrative: the Chicago Board Options Exchange background and 1964 Illinois start, the 1990 retirement and Florida home, the 1995 Illinois lot purchase abandoned in August in favor of an addition to the longtime Illinois home, the November 1995 Florida declaration of domicile, the roughly 1.9 million dollars of Illinois tax and penalties at stake for 1996 through 2004, the Florida licenses, permanent resident identification cards, voter registration, jury summonses, firearm license, cell phone numbers and newspaper delivery, the 73 percent of credit card expenditures and 61 percent of transactions outside Illinois, the shift in charitable giving, the Illinois tax preparers and Illinois political contributions, Mrs. Cain’s unamended Illinois interior designer license renewals, the 1,700 Florida days against 1,666 Illinois days and 284 elsewhere, the 236,000 dollars of Illinois club spending against 422,000 dollars in Florida, the Florida burial plots, the use of the Viking Dodge Inc. v. Hoffman, 497 N.E.2d 1346 (Ill. App. Ct. 1986) four-part change-of-domicile test, the treatment of the physical abandonment and intent-not-to-return factors as indeterminate on a roughly even day split, and the nexus analysis applied to the temporary or transitory question. The detailed account and the academic criticism of the court’s departure from Viking Dodge, which had placed the burden on the taxpayer to establish all four factors, are from Ronald Z. Domsky, Changing Residency for Illinois Tax Purposes, 40 S. Ill. U. L.J. 11 (2015): https://law.siu.edu/_common/documents/law-journal/articles-2015/fall-2015/6-domsky-article-final-approved-sm.pdf.

Illinois Department of Revenue administrative hearing decision IT 24-02, dated April 2, 2024, is the source of the quoted subsection (f) presumption language, the Notice of Deficiency dated June 24, 2019 for tax year 2013 based on the Illinois address on the taxpayers’ federal return and the absence of an Illinois return, the December 21, 2022 evidentiary hearing, the homestead exemption that carried over in the taxpayer’s late mother’s name, the 35 ILCS 200/15-175(i) point that counties determine eligibility by application, visual inspection, questionnaire or other reasonable methods, the observation that in many counties the exemption renews automatically until removed or the property is sold, the Domsky trap for the unwary characterization, and the recommendation that the Notice be cancelled: https://taxarchive.illinois.gov/content/dam/soi/en/web/taxarchive/research/legal/administrative-hearings/it/it-24-02.pdf.

The General Homestead Exemption maximum reductions of 10,000 dollars in counties with 3,000,000 or more inhabitants and 6,000 dollars in all other counties for taxable years 2023 and thereafter, together with the principal dwelling place occupancy and property tax liability requirements, are 35 ILCS 200/15-175: https://codes.findlaw.com/il/chapter-35-revenue/il-st-sect-35-200-15-175/. The erroneous homestead exemption recovery provisions for counties with 3,000,000 or more inhabitants, including the definition of an erroneous homestead exemption, the 3 and 6 collection year lookbacks, the 10 percent interest per annum, the 50 percent penalty where three or more erroneous exemptions were received, the notice of discovery and notice of intent to record a lien with 30 days to pay, and the 60-day self-report safe harbor from penalties, are 35 ILCS 200/9-275: https://codes.findlaw.com/il/chapter-35-revenue/il-st-sect-35-200-9-275/.

The 2025 change allocating a nonresident’s gain or loss on the sale or exchange of Subchapter S corporation shares or of a partnership interest, other than an investment partnership, to Illinois in proportion to the average of the entity’s Illinois apportionment factor in the year of sale and the two preceding tax years, effective for tax years ending on or after June 16, 2025 under Public Act 104-0006 and codified at 35 ILCS 5/303(b)(4), together with the Finnigan method adoption and the 50 percent GILTI dividend deduction cap effective for tax years ending on or after December 31, 2025, is described in Illinois Department of Revenue Informational Bulletin FY 2025-29, Legislative Income Tax Changes that May Increase Current Tax Year Liabilities: https://tax.illinois.gov/research/publications/bulletins/fy-2025-29.html. The worked illustration that a 75 percent three-year average apportionment makes 75 percent of the gain Illinois income is from Sandberg Phoenix: https://sandbergphoenix.com/mid-year-illinois-tax-change-for-sale-of-pass-through-entity-interests/.

The 1.5 percent personal property replacement income tax rate for partnerships and S corporations on income taxable to Illinois, the pass-through withholding obligation for nonresident members of entities that have not elected to pay PTE tax, the Schedule K-1-P and K-1-T reporting with the K-1-P(3) and K-1-T(3) calculations, and Form IL-1000-E as the Certificate of Exemption for Pass-through Withholding under which a member certifies it will file all Illinois returns and pay all Illinois taxes due, are from Illinois Department of Revenue Publication 129, Pass-through Entity Information: https://tax.illinois.gov/research/publications/pubs/pass-through-information.html. The PTE tax election at 4.95 percent of net income made on Form IL-1065 or IL-1120-ST for tax years ending on or after December 31, 2021, and the matching 4.95 percent credit for each owner against their own tax on their distributive share, are from the Department’s partnership guidance: https://tax.illinois.gov/research/taxinformation/income/partnership.html.

The Schedule NR list of Illinois-source income for nonresidents and part-year residents, covering Illinois wages, business income under the apportionment worksheet, Schedule K-1-P and K-1-T partnership and S corporation income, gains on real or tangible personal property located in Illinois, Illinois rental and farm income, Illinois unemployment compensation, and Illinois lottery and gambling winnings, is from the Schedule NR instructions: https://tax.illinois.gov/forms/incometax/currentyear/individual/il-1040-schedule-nr-instr.html. The requirement that part-year residents and nonresidents file Form IL-1040 with Schedule NR, and the Iowa, Kentucky, Michigan and Wisconsin reciprocal agreements, are on the Department’s filing requirements page: https://tax.illinois.gov/individuals/filingrequirements.html.

The 4,000,000 dollar Illinois estate tax exclusion as a taxable threshold rather than a credit, the Form 700 filing requirement where the gross estate exceeds that amount after inclusion of adjusted taxable gifts whether or not a federal return is required, and the treatment of both resident and nonresident decedents through a preliminary tax computed as if all assets were in Illinois and then apportioned by the ratio of Illinois assets to total assets with the Form 700 Addendum, are from the Illinois Attorney General’s Important Notice Regarding Illinois Estate Tax and Fact Sheet: https://illinoisattorneygeneral.gov/Page-Attachments/EstateTaxInstructionFactSheet.pdf.

Florida’s Declaration of Domicile is Fla. Stat. section 222.17. The homestead exemption mechanics, including ownership and occupancy as of January 1, the March 1 filing deadline, the 50,000 dollar reduction split between all taxing authorities and non-school levies, and the proof of permanent residency requirements including proof of not claiming a residency-based benefit in another state, are in the Florida Department of Revenue guidance at https://floridarevenue.com/property/documents/pt113.pdf, with the 30-day driver license and 10-day vehicle registration deadlines from https://www.flhsmv.gov/new-resident/ and the 29-day voter registration rule from https://registertovoteflorida.gov/.

The Illinois and Florida exit stickiness and audit aggressiveness ratings, the description of the Department opening residency inquiries around triggering events rather than broad sweeps, the enforcement method inventory, the three-year, six-year and unlimited assessment periods, the commonly missed exit mistakes including continuing board seats, LLC management and S corporation officer duties, the full exemption of Illinois retirement income, and the roughly 1.92 percent effective property tax rate come from ResidencyIQ’s own dossier research, with underlying citations on the Illinois and Florida residency guides.