See what changed in an Excel model since last month
Updated: October 20, 2026
Month-end comes round, the forecast has moved, and someone asks what changed since last month's version. Excel can tell you that a file changed, but not which cells. This page shows three ways to get the cell-by-cell answer with SheetTrack, a free Excel add-in, coming soon to Microsoft AppSource. None of them changes your workbook.
If last month's version is in OneDrive
OneDrive keeps earlier versions of every workbook saved in it, with no setup. In SheetTrack's Changes tab, choose Since → Choose a OneDrive version… and pick the version from last month. Changes then lists every value and formula that is different since then, each named by its row and column ("Revenue growth · FY27").
This works for a workbook in your own OneDrive, tracked or not. The version is read in SheetTrack on your computer; nothing is sent to SheetTrack. For a workbook on a SharePoint site or in someone else's OneDrive, it works once your IT admin has approved SheetTrack; until then, download last month's version from Version history in OneDrive or SharePoint and use the next way.
If last month's version is a file
Choose Since → Choose a file… and pick last month's copy (.xlsx or .xlsm). Changes lists what is different in the open workbook from that file. The file is read on your computer and is not uploaded.
From now on: save a version at each month-end
Choose Start Tracking once, then Save Version at each close with a note such as "September close". Next month, Since offers every saved version, and Version History compares any two.
What you see
- Key numbers first. Watch the numbers you check first, such as EBITDA or closing cash, and Changes shows each one old → new, with the changes that feed it and, where SheetTrack can recalculate it, each one's share of the move.
- Moves, not noise. Inserted rows, sorted rows and renamed sheets are each one line, not hundreds of cells.
- New problems. Formula errors and broken references that appeared since then are listed under the changes.
- Copy summary gives a short note of what changed, ready to paste into an email.
Formatting, charts, pivot tables and comments are not compared. See the support page for the details.