To display a check mark if a value is valid based on an existing list of allowed values, you can use a formula based on the IF function together with the COUNTIF function. In the example shown, the formula in C5 is: =IF(COUNTIF(list,B5),"✓","") where list is the named range E5:E9. As the formula is copied down, it returns a checkmark when the value in column B exists in the range E5:E9, and an empty string ("") otherwise.