Tom’s Tutorials For Excel: Formatting Cell Contents as Invisible
Here’s how you can make a cell’s contents be invisible, while keeping the cell’s rows and/or columns unhidden. In the following pair of pictures, employee salaries are in column F, but you want them hidden while column F remains visible.

Sometimes you’ll see attempts to accomplish this with Conditional Formatting for white font color. This tactic has limited usefulness, because a cell’s contents are discernible through the selection highlight, and printing the document on colored paper will show the contents.
Nothing is foolproof, but here’s a more reliable method:
Step 1
Select the range of interest, and press Alt+O+E to show the Format Cells dialog box.

Step 2
• In the Format Cells dialog box, on the Number tab in the Category list, select Custom.
• In the Type field, enter ;;; (that is, three semicolons).

Step 3
• On the Protection tab, check the boxes next to Locked and Hidden.
• Click OK.

Step 4
Press Alt+T+P+P to show the Protect Sheet dialog box.

Step 5
• In the Protect Sheet dialog box, select “Protect worksheet and contents of locked cells”.
• A password is optional.
• Put a checkmark in the box next to “Select locked cells.”
• Put a checkmark in the box(es) next to other preferred option(s).
