.NMBTEMPLATE File Extension

Spreadsheet template created by Numbers, an Apple iWork spreadsheet application; saves the layout and cell formatting of the one or more sheets in the workbook; often used to pre-populate the styles and equations required for logging work hours, tracking tasks, and preparing budgets.

NMBTEMPLATES can be created by choosing File → Save As Template.... After a Number template is opened, the spreadsheet can be saved to a .NUMBERS file.