If the Excel Date Filter is not grouping by month, enable grouping dates in the AutoFilter menu, set dates in the proper format, etc.

Excel Group feature allows users to group rows or columns. Ungroup is used to ungroup a range of cells or data that were previously grouped.

Learn how to add a highlight to expose groups in your Microsoft Excel data using a helper column and Excel’s conditional formatting feature.

How to create a grouped PivotTable in Excel Grouping is what Excel’s PivotTable objects do, and it’s easy to summarize groups of data using any number of functions.