End of Session September Budget Package: How, Why, and What Does it Mean? 

With the Legislature’s June 15 deadline to pass a balanced budget nearly three months behind us, it would be reasonable to assume that California’s spending plan for the 2025-26 fiscal year has long been set in stone. The introduction of eighteen new budget bills during the last week of the 2025 Legislative session, which amend the 2025 Budget Act and include new appropriations and implementation measures, proves that assumption wrong. So, how does the state extend the budget-making process into the fall despite constitutional deadlines, and what does this new budget package mean for county governments? Let’s investigate. 

What Happened this Week? 
This week, just before the end of the 2025 Legislative Session, the Legislature added eighteen bills to their already daunting workload in the form of a September Budget Package. An analysis of the package released by the Assembly Budget Committee on Tuesday characterizes it  as “a continuation of June budget discussions,” explaining that “The June 2025 budget package deferred action on some items to allow more deliberation, with the intent that the Legislature would revisit the budget at the end of the 2025 Legislative Session.“  Items of significance include the allocation of Proposition 4 bond funds and actions offsetting projected costs of the federal government’s enactment of HR 1.  

This late package of new budget bills is unusual given its magnitude, but not entirely without precedent.  A look at California’s budget process shows how the Legislature is able to defer action and extend budget negotiations through the end of session.  

The California Budget: a Sum of Parts 
California’s budget is a process rather than a singular product. For example, on June 15, the Legislature enrolled the 2025 Budget Act, meeting the annual deadline for the passage of a balanced budget set by Proposition 25 (2010). While this massive bill included the bulk of the state’s funding appropriations, it was passed with an understanding that additional implementation language and adjustments would be included in budget trailer bills. This is possible thanks to secondary budget bills not beholden to the June 15 deadline, colloquially the budget trailer bills and budget bill(s) junior. Budget trailer bills pertain to specific topics like health, education, or labor, providing additional implementation language for policies consistent with the budget act, whereas budget bills junior amend the budget acts themselves.  

By the time the 2025 Budget Act was signed by the Governor on June 27, more than twenty budget trailer bills and a budget bill junior were also on their way to enrollment. While there is no deadline for the Legislature to approve budget trailer bills similar to the constitutional deadlines for the budget act bills, they are generally passed by the end of June, with negotiations on especially controversial trailer bills sometimes extending into July or August. Thanks to an exemption provided for urgency clause bills, which take effect as soon as they are enacted, the bills related to the state budget are not subject to the August 29^th deadline for fiscal committees to meet and report bills to the floor, as previously reported by CSAC. 

Read CSAC’s comprehensive analysis of the 2025 Budget Act and accompanying trailer bills in our Budget Action Bulletin.  

End of Session Budget Package Tracking 
CSAC’s legislative affairs team will continue to track this last-minute budget package and engage with lawmakers on important issues as the end of session unfolds. Listed below are the budget bills introduced this week as well as summaries of provisions particularly important to county governments. For questions about specific bills or other policy issues, please contact the CSAC Legislative Affairs team.