In Excel, the standard procedure to display nothing in a cell is to use the "" (empty string) in formulas. However, this approach does not literally leave the cell blank—it simply shows nothing. This can cause confusion with functions like ISBLANK which specifically test if a cell contains absolutely no data. For instance, the following formula does not technically leave the cell blank when the IF condition is false:


This will display nothing in the cell but ISBLANK will return FALSE, because the cell contains a formula—the empty string is considered a piece of data.
I need a way to construct an IF statement such that the cell is truly blank if the condition is false, ensuring that ISBLANK returns TRUE.

The Excel formula structure doesn’t allow you to truly leave a cell blank as a result of a formula. When you use "", Excel interprets it as an empty string, nevertheless containing data. If you want ISBLANK to return TRUE, you cannot have any formula in the cell.
However, you could use a VBA macro to achieve this functionality. Here’s a simple example that you can run. This macro checks the condition and only enters a value in the target cell if the condition is TRUE. If the condition is FALSE, it leaves the cell truly blank:


Remember, you will need to run this macro each time you want to check the condition, as opposed to a formula which recalculates automatically.

Agreed with coding_Savvy. If you're set on using only formula and want ISBLANK to return TRUE, there's no direct function in Excel to achieve this. You could bypass the issue by using other techniques, such as Conditional Formatting to hide data or using a helper column that checks whether the cell seems blank and returns TRUE/FALSE based on that. For example, using a helper column that checks if the length of the cell's value equals zero:


This will return TRUE if C1 contains an empty string or only whitespace, but note that technically, the cell isn't blank—it still contains a formula or an empty string, which will be the result of any IF function that evaluates to FALSE.