In Illinois, what constitutes doing business is defined backward: the statutes don’t list the activities that trigger registration, they list the activities that don’t. If your company’s in-state footprint goes beyond those safe harbors, you are transacting business and must get authority from the Secretary of State before you start. This applies to foreign corporations under the Business Corporation Act and to foreign LLCs under the Limited Liability Company Act, and the courts look at whether activity is continuous, systematic, and aimed at generating revenue in the state.1Justia Law. Illinois Code 805 ILCS 5 – Business Corporation Act of 1983, Article 13
How the Rule Actually Works
The Business Corporation Act requires every for-profit foreign corporation to obtain authority from the Secretary of State before transacting business in Illinois. The statute does not spell out an affirmative definition. Instead, a separate section lists specific activities that do not count as transacting business, and the Illinois General Assembly makes clear the list is not exhaustive — other activities may also fall outside the definition.2Illinois General Assembly. Illinois Code 805 ILCS 5/13.75 – Activities That Do Not Constitute Transacting Business
One-off contacts rarely require registration. Repeated cycles of soliciting customers, negotiating contracts, delivering services, or managing property from within Illinois generally do. The practical question is always whether your activity fits inside a safe harbor or goes beyond one.
Activities That Do Not Count as Transacting Business
Section 13.75 lists the activities a foreign corporation can carry on in Illinois without being treated as doing business there:2Illinois General Assembly. Illinois Code 805 ILCS 5/13.75 – Activities That Do Not Constitute Transacting Business
- Maintaining, defending, or settling court proceedings.
- Holding board of directors or shareholder meetings.
- Opening and maintaining Illinois bank accounts.
- Maintaining offices or agents for the transfer and registration of the corporation’s own securities.
- Selling through independent contractors rather than employees.
- Soliciting orders in Illinois when those orders must be accepted outside the state before they become binding contracts.
- Owning real or personal property “without more.”
- Conducting an isolated transaction that is completed within 120 days and is not part of a pattern of similar deals.
- Having a corporate officer or director who lives in Illinois.
Two of those phrases carry most of the weight. “Without more” means passive title only: hold a building and do nothing with it, and you’re safe; lease it, warehouse goods in it, or staff it, and you have moved into active business. The order-solicitation safe harbor hinges entirely on where acceptance happens. If your sales team takes orders in Illinois and those orders become binding before leaving the state, the protection is gone.
Where Companies Cross the Line
Most companies that get caught are not ignoring the rule. They are operating near the edges of the safe harbors and don’t realize they have moved past one. A few patterns come up repeatedly.
Employees Versus Contractors
Selling through independent contractors is protected. Hiring W-2 employees who work from Illinois, even remotely, creates a physical presence that almost certainly requires registration. If a contractor relationship has drifted into something that looks like employment, or if your “contractors” would be classified as employees under Illinois law, the safe harbor may not hold.
Where the Order Is Accepted
Companies commonly instruct sales teams to solicit orders in Illinois while accepting them at headquarters in another state. That structure works under Section 13.75 when it is real. If the Illinois-based salesperson has actual authority to bind the company, or if the out-of-state “acceptance” is a rubber stamp, a court may find that acceptance is happening in Illinois.
Repeated “Isolated” Transactions
A single deal wrapped up within 120 days is protected, but only if it is not part of a pattern. Structuring each Illinois deal as a separate isolated transaction, quarter after quarter, is exactly the repeated activity the safe harbor was designed to exclude.
Active Property Management
The passive-ownership safe harbor evaporates as soon as you begin commercially operating the property. Leasing to tenants, running warehouse operations, or staffing an Illinois location generally puts you in active business territory.
The Same Framework Applies to Foreign LLCs
The Limited Liability Company Act imposes a parallel requirement: before transacting business in Illinois, a foreign LLC must be admitted by the Secretary of State.3Illinois General Assembly. Illinois Code 805 ILCS 180/45-5 – Admission to Transact Business The LLC safe harbor list under Section 45-47 is nearly identical to the corporate version, covering lawsuits, internal meetings, bank accounts, securities offices, independent contractors, out-of-state order acceptance, passive property ownership, isolated transactions, and having a member or manager who lives in Illinois.4Illinois General Assembly. Illinois Code 805 ILCS 180/45-47 – Activities Not Constituting Transacting Business The analysis is the same: check whether your Illinois activity fits inside the safe harbors, and register before you start if it doesn’t.
What Happens If You Don’t Register
The consequences are significant, and they differ somewhat between corporations and LLCs.
Corporations
A foreign corporation operating without authority cannot maintain a civil action in any Illinois court until it registers. The bar extends to any successor or assignee trying to enforce claims that arose from the unauthorized Illinois business. Contracts remain valid and you can still defend lawsuits filed against you.5Justia Law. Illinois Code 805 ILCS 5 – Business Corporation Act of 1983, Article 13 – Section 13.70
Financially, the corporation owes all fees, franchise taxes, and penalties it would have paid if it had registered on time. A corporation that fails to file within 60 days of starting Illinois operations faces an additional penalty: 10% of the total fees owed, or $200 plus $5 for every month of unauthorized business, whichever is greater. The Attorney General can bring enforcement proceedings to collect and can move to restrain the corporation from continuing to do business.
There is also a jurisdictional consequence. A corporation transacting business without authority is deemed to have consented to general jurisdiction in Illinois, the same as if it had registered. That consent attaches upon committing any act of unauthorized business and lasts 180 days after each such act.
LLCs
Foreign LLCs face the same court-access bar: no civil actions until admitted. Contracts stay valid; defense of lawsuits is unaffected.6Justia Law. Illinois Code 805 ILCS 180 – Limited Liability Company Act, Article 45 – Section 45-45
The monetary penalties for LLCs are steeper. An LLC that fails to register within 60 days of starting Illinois business faces a flat $2,000 penalty plus $100 for each month it continues without registration. An LLC operating unauthorized for two years is looking at $4,400 in penalties alone, before back-dated fees. The Attorney General has the same enforcement authority as with corporations.
The practical cost is not just the money. If a customer owes you $500,000 and you need to sue in Illinois, you cannot even file the case until you register. When you do register, you owe back-dated fees and penalties for the whole unauthorized period. Leverage shifts to the other side.
How to Register If You Need To
A foreign corporation files an Application for Authority using Form BCA 13.15. The form asks for the corporate name (with an assumed name if the real one is not distinguishable from an entity already on file in Illinois), incorporation date and duration, principal office address, Illinois registered agent and office, business purposes, directors and officers, share and capital information, and dollar estimates of property and gross business in Illinois and everywhere. The minimum fee is $150, and additional franchise tax may apply based on capital allocated to Illinois.7Illinois Secretary of State. Application for Authority to Transact Business in Illinois
A foreign LLC files Form LLC 45.5, providing the LLC’s name, jurisdiction and date of formation, principal office address, Illinois registered agent details, business purposes, and management structure. A certificate of existence from the home state must be included. The filing fee is $150, with expedited processing available for an additional $100.8Illinois Secretary of State. Limited Liability Company Publications and Forms
Both entity types must continuously maintain a registered agent and registered office in Illinois. The registered office must have a street or rural route address; a P.O. box does not satisfy the statute.9Justia Law. Illinois Code 805 ILCS 5 – Business Corporation Act of 1983, Article 5 Registration also brings an annual report obligation, and failing to file annual reports can eventually revoke your authority, putting you back in the unregistered position.10Illinois Secretary of State. Foreign Corporation Annual Report
Sales Tax Is a Separate Question
The Secretary of State analysis and the sales tax obligation are two different things, and they can hit at different times. Even a company with no physical presence in Illinois may need to register with the Illinois Department of Revenue for sales tax if it exceeds the economic nexus threshold. As of January 1, 2026, remote retailers and marketplace facilitators must collect and remit Illinois sales tax if they have $100,000 or more in cumulative gross receipts from sales of tangible personal property to Illinois purchasers during the applicable lookback period. The previous 200-transaction alternative trigger has been eliminated.11Illinois Department of Revenue. FY 2026-12, Destination-Based Retailers Occupation Tax Changes
Federal Public Law 86-272 offers a narrower protection: it bars states from imposing a net income tax on companies whose only in-state activity is soliciting orders for tangible personal property that are accepted and filled from outside the state. It doesn’t cover services, digital products, or licensing of intangibles, and it doesn’t shield you from sales tax, franchise tax, or the Secretary of State registration requirement.