Files with the .XLAM extension contain add-in with enabled macros, which provide additional functionality and tools for macro execution in Microsoft Excel, an application that allows its users to create and edit spreadsheets. XLAM format is similar to other spreadsheets. It can contain charts, formulas, images, text and more.

XLAM files have been used to expand the standard modules found in Excel since 2007. The files can also be applied to earlier versions of Excel, provided that they include an Open XML element support component.