.XLTX File Extension

Template file created by Microsoft Excel, a program used for creating spreadsheets; contains default settings and layout information used to create a .XLSX file; may be used to create multiple spreadsheets with common formatting and properties.

XLTX files are stored based on the Open XML file format that was introduced with Microsoft Office 2007. They can be opened by Excel 2007 or later, or by previous versions of Excel with Open XML component support.