TLDR
An Illinois 501(c)(3) public charity must (1) incorporate as an Illinois not-for-profit corporation under 805 ILCS 105 ($50 with the Secretary of State), (2) obtain federal 501(c)(3) recognition from the IRS via Form 1023 or 1023-EZ, (3) register with the Illinois Attorney General Charitable Trust Bureau using Form CO-1 ($15) before any solicitation, and (4) file Form AG990-IL annually within six months after fiscal year end. Audited financial statements are required at $300,000 in contributions — one of the lower thresholds nationally. Failure to register before solicitation triggers AG enforcement and inclusion on the public delinquency list.
A new Illinois nonprofit incorporated in October, received its IRS determination letter in February, and ran a year-end giving campaign in November before either registration was complete. In March, the Illinois Attorney General’s office sent a notice citing unregistered solicitation under the Solicitation for Charity Act. The campaign had to be paused, retroactive Form CO-1 filed, and a corrective response submitted — losing the entire spring fundraising window during the AG’s review.
Illinois enforces charitable registration aggressively, and the audit threshold ($300,000 in contributions) is one of the lowest in the country. These 13 questions cover what every Executive Director and Finance Manager operating in Illinois needs to know.
Registration is required before solicitation, not after
The most common Illinois compliance error is treating CO-1 as a post-launch task. The Solicitation for Charity Act (225 ILCS 460) requires registration before any solicitation in Illinois. The clock starts when the first solicitation goes out — direct mail, email appeal, social ad campaign, donate page promotion — not when the IRS determination letter arrives.
AG990-IL is due six months after fiscal year end
This is the Illinois compliance fact that surprises most multi-state organizations. While federal Form 990 is due 4.5 months after fiscal year end, the Illinois AG990-IL is due six months after — six weeks later. For calendar-year filers, the deadline is June 30, not May 15. Calendar this precisely.
The $300,000 audit threshold is a hard line
The Solicitation for Charity Act requires audited financial statements prepared by an independent CPA at $300,000 in contributions. Reviewed financial statements (CPA SSARS review) are required between $25,000 and $300,000. Below $25,000, internal financials suffice. The audit threshold is binding regardless of overall organizational size — an organization with $400,000 in contributions and $2 million in earned revenue is still subject to the audit requirement.
CPA review at $25,000 is also required
Illinois is unusual in requiring CPA review at the relatively low $25,000 contributions threshold. Most states have no review requirement at this level. The review is less expensive than an audit — typically $3,000 to $10,000 — but still requires an engaged CPA firm and adds professional fees that small organizations often do not budget for.
Three separate annual filings
Every Illinois 501(c)(3) has three independent annual filings:
- Illinois SOS annual report — anniversary of incorporation, $10 fee
- Federal Form 990, 990-EZ, or 990-N — May 15 for calendar-year filers, IRS
- AG990-IL — June 30 for calendar-year filers, Illinois AG with attached Form 990
Missing any one is a separate compliance failure with separate consequences. Calendar all three.
Form CO-1 covers initial registration only
Once CO-1 is filed and the AG issues a CO-####### registration number, that registration is active. The annual filing thereafter is AG990-IL — not a renewed CO-1. Some organizations re-file CO-1 annually by mistake; the correct annual filing is AG990-IL.
Pass-through funding from Illinois agencies carries federal compliance
Illinois Department of Human Services (DHS), Department of Children and Family Services (DCFS), Department of Commerce and Economic Opportunity (DCEO), Illinois Criminal Justice Information Authority (ICJIA), and Department of Public Health route significant federal HHS, HUD, DOJ, and other dollars through nonprofit subrecipients. Those funds carry 2 CFR 200 — the federal Uniform Guidance — including restricted fund accounting, allowable cost documentation, and Single Audit exposure at $1,000,000 in federal expenditures for fiscal years ending September 30, 2025 or later.
Online platforms and Illinois-targeted appeals
Donor management platforms and email service providers default to including all subscribers in solicitation campaigns unless explicitly segmented. A national email list will include Illinois residents. An unregistered organization soliciting that list is in violation. Either register with the AG or segment Illinois residents out of solicitation campaigns until registration is active.
Religious organization exemption is narrow
Some religious organizations are exempt under 760 ILCS 55/3, but the exemption is specific. Verify with the Charitable Trust Bureau before claiming it. Organizations that incorrectly assume exemption and solicit without registration face retroactive registration requirements plus penalties.
Suspension and reinstatement consequences
Continued non-filing of AG990-IL leads to administrative suspension. A suspended organization loses the right to solicit donations in Illinois, may be removed from public registry searches that funders verify, and must pay all back fees plus penalties to reinstate. The AG’s public delinquency list is checked by Illinois community foundations and many private foundations during due diligence.
Practical sequence for new Illinois nonprofits
File the Articles of Incorporation with Illinois SOS under 805 ILCS 105. Obtain the EIN. Adopt bylaws and appoint at least three directors. File Form 1023 or 1023-EZ with the IRS for 501(c)(3) recognition. File Form CO-1 with the Illinois AG before any solicitation. Apply for Illinois sales tax exemption with Form STAX-1 once IRS determination is issued. Calendar AG990-IL for June 30 each year (calendar-year filers). Engage a CPA firm well before $250,000 in contributions; auditors at capacity January through April.
Records retention
Illinois Charitable Trust Act and Solicitation for Charity Act require records sufficient to verify all AG990-IL reporting. Standard practice: retain financial records for at least seven years, board minutes permanently, and donor restrictions documentation for the life of the restriction plus seven years after release. The AG can audit and request supporting documentation for any line item.
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- Form CO-1
- Charitable Organization Registration Statement filed with the Illinois Attorney General Charitable Trust Bureau as initial registration. $15 fee.
DEFINITION
- Form AG990-IL
- Illinois Charitable Organization Annual Report. Filed annually with the Illinois AG Charitable Trust Bureau, due 6 months after fiscal year end.
DEFINITION
- Charitable Trust Bureau
- The Illinois Attorney General office unit administering charitable organization registration and oversight under the Charitable Trust Act and Solicitation for Charity Act.
DEFINITION
- Form STAX-1
- Illinois Department of Revenue application for sales tax exemption (E) number. Filed by 501(c)(3) organizations after IRS determination.
DEFINITION
“Illinois's six-month AG990-IL deadline is the trap for organizations expanding from other states. The team calendars off May 15 by habit and misses June 30 entirely.”
“The $300,000 audit threshold is well below the federal Single Audit threshold and below most state thresholds. Plan for the additional CPA cost as soon as the organization is on track to cross that line.”
Frequently asked