@Lukereeves The formula syntax seems to be correct and FILTER looks at the values of the cells to be included, not the formulas in those cells.
You say the function "does not return a value". But you don't specify the result that is being returned. It can't be just nothing. Perhaps a #CALC! error, meaning no matching records were found. If so, you may add a third optional argument specifying what needs to be returned if no matches are found.
Or do you get a dialogue box stating "There's a problem with this formula"? Perhaps you need you use a semi-colon rather than a comma to separate arguments in your local Excel set-up.
