How to Strike Through a Beamer Item After It Appears

To show a Beamer list item normally and then strike through its text on a later slide, use an overlay command to switch between the ordinary text and a struck-through version. The item and its bullet can remain on screen throughout.

Minimal working example

The \sout command comes from the ulem package. The normalem option prevents ulem from changing the usual behavior of \emph.

\documentclass{beamer}
\usepackage[normalem]{ulem}

\begin{document}

\begin{frame}{A task list}
  \begin{itemize}
    \item \alt<2->{\sout{Submit the report}}{Submit the report}
    \item Check the references
  \end{itemize}
\end{frame}

\end{document}

On overlay 1, “Submit the report” appears normally. From overlay 2 onward, the same text is crossed out. The second item remains unchanged.

How the overlay works

The syntax is:

\alt<2->{content for overlay 2 onward}{content for other overlays}

In this example, \sout{Submit the report} is selected starting on overlay 2, while the plain text is selected on overlay 1. The 2- range means overlay 2 and every later overlay in that frame. Change the number to choose a different point: for example, <3-> starts the strike-through on overlay 3.

The \alt command belongs to Beamer, so no extra overlay package is needed. The \sout command belongs to ulem, which is why the example loads that package.

Strike through an entire item

The example strikes through only the item’s words; the bullet stays visible. That is usually clearer because it keeps the list structure stable. If you also want to change the bullet or the whole item’s appearance, apply overlay specifications to the item itself or configure the item’s color separately. For simply crossing out the text, keep \alt after \item as shown.

Common mistakes

• Forgetting to load ulem: LaTeX will not know the \sout command. Add \usepackage[normalem]{ulem} in the preamble.
• Using \sout on a math expression: \sout is intended for text. For mathematical notation, a math-cancellation command such as \cancel from the cancel package is more appropriate; it draws a diagonal cancellation mark.
• Using the wrong overlay number: Overlay numbers start at 1 within each frame. Use <2-> to change the text on the second displayed version of that frame, not the second frame in the presentation.
• Leaving out one branch of \alt: The first branch is shown on the specified overlays, and the second is shown on the others. Include both versions if the text should remain visible before the strike-through begins.