Can I set a password on a spreadsheet?

Yes – Microsoft Excel allows you to protect a workbook or worksheet with a password. This feature exists in all modern versions of Excel, including older releases such as Office 2003.
Before you set a password, keep two things in mind:

• If you lose or forget the password, you cannot recover it.
• Passwords are case‑sensitive.

Password options in Excel

Excel offers two main types of protection:
Password to open
This prevents anyone from opening the file without the correct password. Use this option if you want to keep the contents completely private.

Password to modify
This allows people to open and view the file, but they cannot make changes unless they enter the modification password. Use this when you want the file to be readable but protected from edits.

How to set a password (modern Excel)

1. Open the spreadsheet you want to protect.
2. Go to File → Info.
3. Select Protect Workbook.
4. Choose either Encrypt with Password (password to open) or Protect Workbook Structure (limits editing).
5. Enter your password and confirm it when prompted

How to set a password (Office 2003)

1. Open the spreadsheet.
2. Click Tools → Options.
3. Select the Security tab.
4. Enter a password to open and/or a password to modify.
5. Click OK, then confirm the password when prompted.

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