9. Links to Other Workbooks

A formula can take data not only from another sheet but from another file. Start typing a formula, switch to the open workbook and click a cell, and Excel writes the reference for you:

• the file name goes in square brackets, followed by the sheet name and !;
• if the workbook or sheet name contains a space, everything before the ! goes in apostrophes, just like for the sheet 'Price List 2026'!B2;
• when the source workbook is closed, Excel adds the full path: ='C:\Reports\[Price List 2026.xlsx]Sheet1'!$B$2;
• references to other workbooks are absolute ($B$2) by default.

Updating. When you open a file with links, Excel shows a warning with an "Enable Content" or "Update" button. The list of all links is under Data › Edit Links (newer versions call it Workbook Links). There you can update them, change the source to another file or break them, which turns the formulas into values.

Pitfalls: if you rename or move the source file, the link breaks (you get #REF! or old values); INDIRECT does not work with a closed workbook; and a colleague without access to the folder will see the last saved numbers. For regular loading of data from files, Power Query is more reliable.

The trainer has no second workbook. The closest equivalent is a reference to a sheet in the same workbook: the syntax is the same, just without the [File.xlsx] part. Here the "Price List 2026" sheet plays the part of an external price list, and the "Rates" sheet plays the part of a file with the exchange rate.