How to break links in Excel

1. Break links with Workbook Links (or Edit Links)

A link is a formula that reads from another file, like ='[Budget 2026.xlsx]Summary'!B4. When you open the workbook, Excel asks whether to update it, and if the other file has moved you get errors or a "This workbook contains links to one or more external sources" prompt.

Breaking a link turns each linked formula into the value it currently shows. It can't be undone with Ctrl+Z, so save a copy of the file first.

1. Save a copy of the workbook (File > Save a Copy).
2. In Microsoft 365, go to Data > Workbook Links. In Excel 2021 and older, go to Data > Edit Links.
3. Select the source file. In the Edit Links dialog you can Ctrl+click to select several sources at once.
4. Click Break Link (in the Workbook Links pane, use the Break links command for that source), confirm, and save.

2. Break Link is greyed out

The usual reason is a protected sheet. Go to Review > Unprotect Sheet on each protected sheet (you'll need the password if one was set), break the link, then protect the sheets again.

If no sheet is protected and Break Link is still greyed out, the link isn't in a cell formula at all. Excel lists it, but it lives in a name, a validation rule or a formatting rule, which Break Link can't convert. The next sections find those.

3. Find links in cell formulas

Every external link contains the source file name in square brackets, so search for the bracket.

1. Press Ctrl+F and click Options.
2. In Find what, type [ (or .xl to match .xlsx, .xlsm and .xls).
3. Set Within to Workbook and Look in to Formulas.
4. Click Find All. The list shows every cell with a link; click one to jump to it.

4. Links hiding in names, validation, rules and charts

These are the ones that survive Break Link and keep the warning coming back. Check each place in the table above.

Names: go to Formulas > Name Manager and sort by Refers To. A name that points to [Other file.xlsx] or a #REF! with a file path is a link; edit it to a local range or delete it if nothing uses it. Names copied in with moved sheets are a very common cause.

Data validation: Home > Find & Select > Data Validation selects every cell with a rule. Check Data > Data Validation for a Source pointing at another file and change it to a local list. Conditional formatting: Home > Conditional Formatting > Manage Rules, with Show formatting rules for set to This Worksheet; look for rules mentioning another file, on every sheet.

Charts: click each data series and read the =SERIES( formula in the formula bar; if it names another workbook, use Select Data to change the range. PivotTables: PivotTable Analyze > Change Data Source. Shapes and buttons can also carry a link through an assigned macro or a cell reference typed in the formula bar.

5. The prompt when the file opens

If you need to keep the links but not the question, the Edit Links dialog has a Startup Prompt button where you choose whether Excel asks, updates silently or doesn't update. There's also a per-user setting, File > Options > Advanced > General > Ask to update automatic links. Turning it off updates links without asking on your computer only; colleagues still get the prompt.

If the links are a leftover, breaking or deleting them is better than hiding the prompt. A workbook with no external links opens faster and can't pull in stale numbers from a file someone moved.