Missouri School Start Date Law: Exemptions and Penalties

Missouri’s school start date law bars public school districts from opening the school year earlier than 14 calendar days before the first Monday in September. Governor Mike Parson signed HB 161 in July 2019, and the restriction took full effect in the 2020–21 school year.¹ A district that starts early loses one quarter of its state funding for every day it was in violation.

Figuring Out the Earliest Legal Start Date

Labor Day always falls on the first Monday in September. Count back 14 calendar days from that Monday, and you have the earliest date any Missouri public school district may begin classes. Because Labor Day shifts, so does the earliest start:

2025: Labor Day is September 1, so the earliest start date is August 18.
2026: Labor Day is September 7, so the earliest start date is August 24.
2027: Labor Day is September 6, so the earliest start date is August 23.

Every public school district in the state works within the same window, so a neighboring district cannot open weeks ahead of yours.¹

What Happens if a District Starts Early

The Missouri Department of Elementary and Secondary Education must withhold an amount equal to one quarter of the state funding the district generated under Section 163.031 for each date the district was in violation.¹ A few days early can translate into a serious hit to the operating budget, which is why districts treat the 14-day rule as a hard line rather than a suggestion.

Before HB 161, local boards could set an earlier start through a public-notice-and-vote process. The 2019 law removed that option, and the statute now says so directly.¹

Who Is Exempt From the Rule

A few schools sit outside the 14-day requirement:

Year-round schools, defined as districts in session for all 12 months of the calendar year, are excluded from the start date and penalty provisions.¹
Private and parochial schools are not covered, because the statute applies to public school districts. They set their own calendars.

Charter schools are public schools under Missouri law. The PRiME Center at Saint Louis University noted that the 2019 law applies to both school districts and charter schools.² If your child attends a Missouri charter school, assume the 14-day rule applies unless the school has received a specific exemption.

State Board Exemptions

The statute leaves one narrow opening. The State Board of Education can grant a district an exemption from the start date requirement if the district shows “highly unusual and extenuating circumstances,” and any exemption granted is valid for a single academic year.¹ A district that needs relief the next year has to apply again. DESE has asked applicants to demonstrate community support, hold a public hearing, and explain how an earlier start benefits students. Approval is not routine.

Minimum Instructional Hours and Days

Missouri measures the school year in hours, not days. Every district must provide at least 1,044 hours of actual pupil attendance. Half-day programs, such as certain kindergarten schedules, must meet a 522-hour floor.¹

Some districts also have to hit a minimum number of school days. Districts located wholly or partially in a county with a charter form of government, or in a city with more than 30,000 residents, must schedule at least 169 school days. Districts on a four-day school week under Section 171.028 must provide at least 142 school days.¹

The hour-based system means a later August start doesn’t automatically push the school year deep into June. Districts can lengthen the school day, trim breaks, or otherwise reshape the calendar to hit 1,044 hours on their preferred end date.

Snow Days and Makeup Time

Missouri weather takes a bite out of most school calendars, and the law plans for it. Every district’s annual calendar must include 36 makeup hours for attendance lost to inclement weather. Section 171.033 defines inclement weather to include ice, snow, extreme cold, excessive heat, flooding, and tornadoes.¹

Districts can also adopt an Alternative Methods of Instruction (AMI) plan approved by DESE. Under an approved AMI plan, students work remotely on days the building is closed, and that time counts toward the 1,044-hour requirement. AMI plans are capped at 36 hours per year. A district that burns through both its built-in makeup hours and its AMI allowance in a rough winter may have to extend the year further into June.

1
Missouri Revisor of Statutes. Missouri Code 171.031 – Board to Prepare Calendar, Minimum Term, Opening Dates, Exemptions
2
PRiME Center | St. Louis University. Missouri’s School Calendar: What’s Best for Kids?