Sum only cells that are filled in

Hi everyone,

I've been looking around for this answer quite some time now, but I can't find the correct formula. My problem is as follows:

In (a large) Excel file, I want to SUM cells L1, U1 and AF1, and so on for every row down (so L2 + U2+ AF2 etc). So the formula I'm using seems logic (=SUM(L1+U1+AF1), but I don't want this formula to calculate a total if none of these cells is filled in. So it's OK when 1 out of these 3 is filled in, then Excel may calculate a total, but when none of them is, I don't want anything to appear in my "total" column.

Anyone who can help?

Thanks!

Thanks for your input, but these formulas are still not working. Any other idea?

Thank you all for your input! I managed it now to do it this way:
=IF(COUNT(L1;U1;AF1)>0;SOM(L3;U3;AF3);"")

This works fine, thanks for your advivce!