Keyboard shortcut for strikethrough in TextEdit.

Hi Chris. Create a user defined app shortcut. Navigate to  > System Preferences > Keyboard > Shortcuts > App Shortcuts and click the ➕ button. Select TextEdit.app as the application, input "Struck through" as the menu title, and press a key combination for the keyboard shortcut. Click Add. Strikethrough isn't available for the plain text format. Using the GUI, strikethrough is available from the Styles drop-down list.

You're welcome Chris. Good solution on the Default shortcut. All the styles from the Styles list only revert by selecting Default when using the Styles list. For those text formatting options (bold, italic, underline, and outline) available from the menu bar by navigating to Format > Font, the available keyboard shortcuts will revert the style even when set from the Styles list.

Mac keyboard shortcuts

Perhaps there isn't one available in TextEdit. I did not find one.