Thank you for all the help so far, I've learn't alot, however I think I've 'snookered' myself... I'm trying to build a costing spreadsheet... If the answer in a specific area is "YES" then I would like the formula to continue... If the answer is "NO" then that specific part of the formula should be halted.

The costing spreadsheet if for my sign shop and I would like the estimator just to type in the size and then tell the programme whether there's a steel frame, poles, paint, etc. and if so continue with the calculations...

Here's the first part... =IF(B5="YES",D5) Here's the formula for D5... =SUM(D2*2+D3*2) but I do not want this formula to occur if the answer is "NO"... This formula I wrote just comes up with "FALSE"... =IF(B5="YES"=SUM(D2*2+D3*2),) even if the answer is "YES"