Expulsion, also known as dismissal, withdrawal, or permanent exclusion (British English), is the permanent removal or banning of a student from a school, school district, college, university, or TAFE due to persistent violation of that institution's rules, or in extreme cases, for a single offense of marked severity. Colloquialisms for expulsion include being "kicked out of school", "expelled", or "sent down". Laws and procedures regarding expulsion vary between countries and states.

The practice of pressuring parents to voluntarily withdraw their child from an educational institution, termed off-rolling in the UK, is comparable to expulsion. Rates of expulsion may be especially high for students of color, even when their behavioral infractions are the same as those of white children. Certain disabilities, such as autism and ADHD, also increase the risk of expulsion, despite the fact that this could constitute unlawful discrimination in many jurisdictions.

In Ireland, a school must notify the local Educational Welfare Officer before expelling a student; they will then try and find a solution. The student cannot be expelled until twenty days after the educational welfare officer has been notified. Under Section 29 of the Education Act 1998 an expelled child's parent(s) may appeal an expulsion to the Secretary General of the Department of Education. The Child and Family Agency (Tusla) may also appeal an expulsion. If the department upholds the expulsion, a further appeal can be brought to the High Court.

In 2017–18, 29 primary school pupils were expelled in Ireland, up from 18 the previous year. In 2015–16, 195 secondary school students were expelled.

In New Zealand, exclusion and expulsion are methods for removing a student from a school for misconduct. Both are governed by sections 13 to 19 of the Education Act 1989, and the Education Stand Down, Suspension, Exclusion, and Expulsion Rules 1999.

The difference between exclusion and expulsion is that students aged under 16 are excluded, while students aged 16 and over are expelled. For students excluded, because they are under the minimum school leaving age, the excluding school is required to find an alternative school for the student to attend, or reinstate the student if another school cannot be found. For students that are expelled, the expelling school is not required to find an alternative school, as the student is over the minimum school leaving age.

Exclusion/expulsion cannot be directly done by the principal. It must be done through suspending the student, and requiring the school's board of trustees, or a standing disciplinary committee of the board, to independently assess whether or not the situation is serious enough to justify exclusion or expulsion of the student.

In 2009, exclusions and expulsions rates were 2.41 and 2.01 per thousand students respectively. Students were more likely to be excluded or expelled if they were male, of Maori or Pacific Island descent, and/or attended a school with a low (1–4) socioeconomic decile.