Chronic absenteeism means a student has missed at least 10 percent of school days, which the National Center for Education Statistics (NCES) says is roughly 18 days in a school year. This explainer covers how the measure is defined, why the national count changed, how it differs from average attendance and truancy, and which strategies federal education researchers highlight.
According to NCES, more than 14 million students in the United States were chronically absent in the 2021–22 school year. That figure is the most recent one on the NCES page reviewed for this article; readers should check NCES for newer releases.
What does chronic absenteeism actually measure?
The measure counts students, not days. A student is chronically absent when the share of school days missed reaches 10 percent or more, according to NCES. The definition covers absences for any reason, so a student who misses school because of illness counts the same way as one who skips class.
That is a different question from the one most people ask about school attendance. A school can post a healthy daily turnout and still have a large group of students who are missing a day here and a day there, because a handful of absences a month never shows up in a single-day headcount.
A worked example
The arithmetic is simple. NCES puts 10 percent of days at “approximately 18 days,” which implies a school year of about 180 days. As illustrative arithmetic only:
- 10 percent of a 180-day year is 18 days.
- A student who misses two days a month over a nine-month school year misses 18 days, which reaches the threshold.
- A student who misses one day a month misses 9 days, or 5 percent of that year, which falls below it.
The 180-day year is an assumption used for illustration; school calendars vary, and the threshold is a percentage of days a student is enrolled, not a fixed number of days.
Why did the national count change?
For years the national definition was a day count. According to notes from the NCES National Forum on Education Statistics, the federal Civil Rights Data Collection (CRDC) began collecting chronic absenteeism data in the 2013–14 school year, defining it as missing 15 or more days. Its first look at those data found over 6 million students, or 13 percent of all students, missed 15 or more days.
Starting with the 2016–17 school year, states were to report through the federal EDFacts system using a percentage: students absent 10 percent or more of school days. The same notes record that forum members welcomed the shift from days to a percentage because it better accounts for transient populations and may reduce underreporting. Nearly all state and local representatives at the meeting said they could already collect the percentage data.
| Measure | Threshold | Where it appeared |
|---|---|---|
| Earlier national count | 15 or more days missed | CRDC, 2013–14 school year |
| Current federal definition | 10 percent or more of school days | EDFacts, starting 2016–17 |
Source: NCES National Forum on Education Statistics meeting notes, summer 2016.
Because the two definitions differ, a 2013–14 figure and a 2021–22 figure should not be compared directly. The 13 percent from the earlier count and the more than 14 million students from the later one measure related but different things.
How is chronic absenteeism different from truancy and average attendance?
Three terms are often mixed up.
- Chronic absenteeism counts all absences, excused or unexcused, as a share of school days.
- Daily average attendance is the number of students who show up each day. NCES forum notes describe it as distinct from chronic absenteeism.
- Truancy is defined state by state and generally focuses on unexcused absences.
The forum notes give Washington State as an example of how states set their own rules. There, chronic absenteeism is missing at least 18 full days (10 percent) for any reason, while truancy is missing five or more full days unexcused in a month, or 10 or more full days unexcused in a school year.
The notes also flag a data-quality problem: excused and unexcused absences, and what counts as “present,” are defined differently across schools. Two schools with the same real attendance can therefore report different numbers.
Why do students miss so much school?
The NCES evidence page does not offer a complete list of causes. It names chronic health challenges and transportation issues as examples of problems families may raise with schools. It also says schools can find the other reasons students miss school through attendance “deep dives,” an approach it attributes to a 2018 regional education laboratory resource.
The practical point is that the causes vary from student to student. A strategy that works for a family facing a transportation problem may do nothing for a student who has fallen behind or feels disconnected, which is why researchers emphasize identifying individual reasons before choosing a fix.
What strategies does federal research support?
NCES, drawing on work from the Institute of Education Sciences (IES), lists several evidence-based approaches.
Text messages to families
The NCES page describes a basic version: a weekly Sunday message about attendance, plus automated same-day texts that include the student’s name and total absences so far that year. For students who were chronically absent before, schools can add direct staff outreach or automated goal-setting texts.
According to NCES, the share of chronically absent students fell by 12 to 18 percent when schools used text messaging, citing studies published in 2020 and 2021. The page also says basic text messaging was, on average, enough to raise overall attendance, and that the results did not depend on how the messages were framed.
Early warning systems
Early warning systems use attendance data to flag students who are chronically absent or at risk of becoming so, so educators can direct help to them. NCES says IES-funded research suggests these systems can help school systems improve attendance. It also cites a 2020 regional study that found machine-learning models identified at-risk students with moderate to high accuracy.
Partnering with families and improving school climate
NCES also points schools to toolkits on engaging families and communities, including a kindergarten-focused attendance toolkit. On climate, it lists reducing exclusionary discipline, building a sense of belonging and social-emotional learning, supporting newcomer students, and using trauma-informed practice and a multi-tiered system of support.
NCES adds that IES recommends reviewing a 2024 guide on continuous improvement before choosing which intervention to adopt.
How do schools track absences day to day?
Practice varies. According to the forum notes, West Virginia records absence data daily in a statewide system, so schools and districts can run real-time reports, and district dashboards show trends and let users filter by student characteristics. The notes describe Rochester, New Hampshire, as convening a school team when a student misses eight half days and reporting attendance data to the school board monthly.
These examples date from 2016 and may have changed. They illustrate the general design: catch the pattern early, involve a team, and make the data visible to decision-makers.
How does this connect to Maryland schools?
Maryland’s public schools operate through a set of local systems, described in the Maryland Herald explainer on how Maryland public schools are organized into 24 school systems. Attendance is tracked locally and reported up, so the definitional issues above, including what counts as “present,” matter at the district level.
For national context on how many students the system serves, see public school enrollment and what NCES data shows. Readers interested in the calendar side of attendance can also read why Maryland public schools start after Labor Day.
Families who want current figures for their own school or district should check the school system’s published attendance data and the Maryland State Department of Education.
Reading attendance numbers with care
Attendance statistics are easy to misread. A few questions help.
- Is the measure a count of days or a percentage of days enrolled?
- Does it include excused absences, or only unexcused ones?
- Is the figure a rate for students, or an average for schools?
- Which school year does it cover, and was the definition the same then?
Asking these questions explains why one report can show a very different attendance picture from another without either being wrong.
What the definition means going forward
Chronic absenteeism is a deliberately broad measure: any reason, 10 percent of days, roughly 18 in a typical year. Its value is that it reveals students whom a daily headcount hides. The federal research summarized by NCES suggests that low-cost steps such as regular text messages to families, and data systems that flag students early, can reduce the number of chronically absent students, though the right approach depends on why a given student is missing school.
This article is general information about education statistics and is not individual advice for any family or school.
Sources: National Center for Education Statistics
