What read-only means and why you'd use it

A read-only file is one that people can open and look at, but cannot change, delete, or save over. In Excel, this means someone can view your spreadsheet, copy numbers from it, print it, or filter the data — but they cannot edit cells, add rows, or modify formulas. The file stays exactly as you left it.

You use read-only when you want to share information without risking accidental changes. A manager might send a read-only budget template so employees see the format but cannot alter the structure. A team might lock a master data file so only one person can update it, while others reference it safely. Read-only is not encryption or password protection — it is a gentler barrier that stops casual edits but does not hide the file contents.

Excel offers two main ways to make a file read-only: you can set it at the file level (the operating system prevents editing), or you can protect the sheet itself (Excel prevents editing). The file-level method is stronger; the sheet-level method is more flexible because you can unlock specific cells.

Key Takeaways

  • File-level read-only (set through Windows or Mac properties) stops anyone from saving changes to the file itself, though they can still edit a copy.
  • Sheet protection (set inside Excel) locks cells and formulas but lets you unlock specific cells so people can edit only what you choose.
  • Read-only is not a password — anyone can remove it if they have access to file properties or know the sheet protection password.
  • The fastest method for sharing is to set the file read-only before sending it, which requires no setup inside Excel.

Making a file read-only at the Windows file level

This method prevents anyone from saving changes back to the original file. They can still open it, edit a copy, and save that copy with a new name — but they cannot overwrite your original.

Right-click the Excel file on your computer and select Properties. At the bottom of the General tab, you will see a checkbox labeled Read-only. Check that box and click explore, then OK. The file is now read-only. When someone opens it in Excel and tries to save, Excel will ask them to save it with a different name or location instead.

To undo this, open Properties again, uncheck Read-only, and click explore. You will need administrator access to your computer to change file properties; if you do not have that, ask your IT department or the computer owner.

Making a file read-only on a Mac

The Mac method is similar but uses different language. Right-click (or Control-click) the Excel file and select Get Info. Scroll down to the bottom and look for a checkbox that says Locked. Check that box and close the window.

On a Mac, a locked file prevents anyone — including you — from saving changes without unlocking it first. If you try to save, Excel will ask you to unlock the file or save a copy. To unlock it later, open Get Info again and uncheck Locked.

Protecting a sheet inside Excel so only certain cells can be edited

This method is more flexible because you can choose which cells people are allowed to change. For example, you might lock all the formulas and headers but leave the data-entry cells unlocked so people can fill in their own numbers.

First, select the cells you want people to be able to edit. Click the first cell, then hold Ctrl (or Cmd on Mac) and click each other cell or drag to select a range. Right-click and select Format Cells. Go to the Protection tab and uncheck the box labeled Locked. Click OK. This marks those cells as unlocked.

Now go to the Review tab (or Sheet tab on Mac) and click Protect Sheet. A dialog box will appear. You can enter a password if you want, but it is optional — the sheet will be protected either way. Click OK. Now all cells except the ones you unlocked are locked. People can click into unlocked cells and type, but they cannot edit locked cells, delete rows, or change formulas.

If you set a password, you will need that same password to unprotect the sheet later. If you did not set one, anyone can unprotect it by going back to Review > Protect Sheet and clicking Unprotect Sheet with no password required. Write down any password you use and store it somewhere safe.

Protecting the entire workbook so sheets cannot be added or deleted

If you want to prevent people from adding new sheets, deleting sheets, or moving sheets around, you can protect the workbook itself. This is different from sheet protection — it locks the structure of the file, not the cells.

Go to the Review tab and click Protect Workbook. A dialog will ask if you want to protect the structure, the windows, or both. Choose Structure to prevent adding, deleting, or moving sheets. You can set a password or leave it blank. Click OK. Now people can edit cells inside sheets, but they cannot change how many sheets exist or rename them.

What read-only does and does not do

Read-only stops accidental changes and casual edits. It does not hide your data, encrypt it, or prevent someone from copying it. Anyone with the file can see every number, formula, and cell comment. If you need to keep information secret, read-only is not the right tool — you would need password-protected encryption instead.

Read-only also does not prevent someone from making a copy of the file and editing that copy. If you email someone a read-only Excel file, they can save it with a new name and edit the copy freely. Read-only only protects the original file you created.

If you remove read-only protection later and want to know whether someone edited a copy, Excel's version history (in OneDrive or SharePoint) can show you changes, but a file sitting on someone's desktop will not. For tracking who changed what, consider using OneDrive or SharePoint instead of email, because those services keep a change log.

Frequently Asked Questions

Can someone remove read-only protection if they have the file?

Yes, if you set it at the file level. They can right-click, open Properties, and uncheck Read-only themselves. If you protected the sheet inside Excel without a password, they can also unprotect it by going to Review > Protect Sheet > Unprotect Sheet. A password makes it harder, but not impossible — determined people can sometimes work around it.

What is the difference between file-level read-only and sheet protection?

File-level read-only (set in Properties) prevents saving changes to the original file — people must save a copy. Sheet protection (set in Excel) locks specific cells so people cannot edit them, but they can still save changes to the file itself. Use file-level for sharing final versions; use sheet protection when you want people to edit some cells but not others.

If I protect a sheet with a password, what happens if I forget it?

You cannot unprotect the sheet without the password. Write down any password you use and store it somewhere you will remember. If you lose it, you would need to recreate the spreadsheet or use a third-party tool to remove the protection, which may not always work.

Can I make a file read-only and still edit it myself?

Yes, but it depends on the method. If you set file-level read-only, you can uncheck it in Properties whenever you need to edit. If you protected the sheet with a password, you can unprotect it with that password. If you protected it without a password, you can unprotect it anytime. Keep your password in a safe place so you do not lock yourself out.

Does read-only work if I share the file through OneDrive or Google Drive?

File-level read-only may not work the same way in cloud storage — the behavior depends on the service and the app being used. For OneDrive and SharePoint, use Excel's built-in sharing permissions instead: share the file with view-only access so people cannot edit it at all. For Google Drive, use the sharing settings to give people Viewer access instead of Editor access.