In Illinois, a bill becomes law after it is read on three separate days in each chamber of the General Assembly, passes both the House and the Senate in identical form, and is either signed by the governor or left unacted-on for 60 calendar days. Vetoes can be overridden, and the effective date depends on when the bill passed. Here is how the process works, and how you can follow or influence a bill along the way.
The Three-Readings Path Through the House and Senate
The Illinois Constitution, in Article IV, Section 8, requires every bill to be read by title on three separate days in each chamber before a final vote. The rule exists to prevent legislation from being rushed through without adequate review.
On first reading, the Clerk of the House or Secretary of the Senate assigns the bill a number and refers it to the chamber’s assignments committee, which decides which substantive committee will hear it. House bills carry an “HB” prefix; Senate bills use “SB.”
Committees do the real scrutiny. Members hear testimony from experts, advocates, and members of the public, then vote on whether the bill deserves a floor debate. A bill that clears committee moves to second reading, where floor amendments can be added. Before second reading, a bill that would spend state money, change state revenue, or shift costs to local governments, school districts, or community colleges must have a fiscal note estimating its financial impact. Third reading is the final vote in that chamber.
If a bill passes one chamber and the second chamber amends it, the changed version goes back to the originating chamber. Both bodies have to vote on identical language before anything reaches the governor’s desk.
One wrinkle worth knowing: not every bill filed contains real policy at introduction. Shell bills, sometimes called vehicle bills, are placeholders that make a trivial change to existing law and reserve a bill number for later use. A floor amendment can replace the placeholder text with substantive language after the filing deadline has passed, letting a proposal advance faster than a bill drafted from scratch. Over a thousand shell bills were filed for the current session.
What the Governor Can Do With a Bill
After both chambers pass a bill, it must be presented to the governor within 30 calendar days. The governor then has 60 calendar days to act. Signing makes it law. Doing nothing for 60 days also makes it law, without a signature. The complexity is in the vetoes.
Full Veto
A full veto rejects the entire bill and returns it to the originating chamber with the governor’s objections. Overriding requires a three-fifths vote of the members elected to each chamber: 71 in the House and 36 in the Senate. Each chamber has 15 calendar days to act once the objections are entered in the journal. If either chamber falls short, the bill dies for that session.
Line-Item and Reduction Vetoes
These apply only to appropriation bills. A line-item veto strikes specific spending items entirely. A reduction veto lowers an amount without eliminating it. Restoring a line-item veto takes the same three-fifths supermajority as a full veto. Restoring a reduced amount takes only a simple majority of the members elected to each chamber: 60 in the House and 30 in the Senate. If the legislature does nothing, the lower amount becomes law automatically.
Amendatory Veto
An amendatory veto returns the bill with the governor’s specific recommendations for changes. The legislature has three choices: accept the recommendations by a simple majority in each chamber, override the veto with a three-fifths vote, or do nothing and let the bill die. If lawmakers accept the changes, the bill goes back to the governor, who must certify that the accepted language matches the original recommendations before it becomes law. For amendatory vetoes issued after May 31 with an immediate effective date, accepting the governor’s changes requires a three-fifths vote rather than a simple majority.
Vetoes are typically taken up during veto session, when the General Assembly reconvenes for two weeks between late October and early November, or later in election years. Lawmakers can also pass new measures during those weeks.
When a New Law Takes Effect
The Effective Date of Laws Act at 5 ILCS 75 sets the default. A bill that passes before June 1 and does not specify its own effective date takes effect on January 1 of the following year. That gap gives agencies, businesses, and the public time to prepare.
Bills passed after May 31 face a stricter rule. Without a three-fifths supermajority in both chambers, they cannot take effect until June 1 of the following year. A bill can specify its own effective date, but if that date is earlier than the default allows and the bill passed after May 31, the earlier date still requires the supermajority. The structure pushes lawmakers to move major legislation before the spring session ends.
How to Look Up and Track a Bill
The official Illinois General Assembly website at ilga.gov is the most reliable source. Under Bills & Resolutions, the Search By Number field pulls up any bill if you already have the number. The Search By Keyword option finds bills related to a topic, and you can also browse everything filed by a specific lawmaker. Check the General Assembly number at the top of the page to be sure you are viewing the current session; the 104th General Assembly covers the 2025–2026 term.
Each bill page displays the full text, any filed amendments, a short synopsis, and a Bill Status page showing every procedural step. The Last Action field lists the most recent move, whether a committee assignment, a floor vote, or delivery to the governor. Committee history includes how individual members voted.
If you are following more than one bill, the site’s My Bills feature builds a personal tracking list and can send email alerts whenever a bill’s status changes or a new amendment is filed. That matters during busy stretches, when dozens of bills can move in a single day. Floor sessions and many committee hearings stream live on ilga.gov, with daily schedules posted on each chamber’s calendar page, usually the evening before.
From Bill Number to Public Act Number
Once signed, a bill receives a Public Act number. The digits before the dash identify the General Assembly that passed it. P.A. 104-0025, for example, would be the 25th public act of the 104th General Assembly. You can search public acts on ilga.gov under Legislation & Laws by choosing “Public Acts – Listing” and selecting the session. A bill’s status page will show its public act number once the governor has signed it.
How to Weigh In on a Bill
Anyone can file a witness slip, the General Assembly’s formal record of public support, opposition, or neutrality on a bill scheduled for a committee hearing. Slips are filed electronically through the dashboard at my.ilga.gov. Creating an account saves your contact information for future filings, but an account is not strictly required.
Witness slips open once a hearing is posted, usually about a week in advance. In the House, you can submit or edit a slip up until the committee hearing concludes. The Senate allows submissions through the end of the day the hearing is scheduled. If a hearing gets rescheduled, previously filed slips do not carry over; you have to file a new one for the new posting.
A witness slip puts your position on the record but does not guarantee you will speak. Oral testimony requires advance coordination with the committee. Senate committees allow remote testimony with the chair’s approval for witnesses who are out of town or have a medical condition preventing in-person attendance, but not for registered lobbyists. Requests must be emailed to the committee’s designated address by noon the day before the hearing, with written testimony attached as a PDF.