I don't know what you mean by "filter out." I am talking about deleting rows in the PR sheet that don't reference an existing Project sheet.

The length of the MR data is insignificant, only ~1000 rows, that will take only milliseconds to loop thru. However, you will be looping at least part way thru the PR data once for every line in the MR data.

If there is no match in PR for any given line(s) in MR, the code must loop all the way thru the PR data. That will take significant time; perhaps seconds each. I can't do anything from here about the time it will take to search and write to each Project sheet, but it would be nice to eliminate as many bottlenecks as possible.

While I wish I could get the code to complete your weekly task in less than 10 seconds, I am hoping that it will take less than 3 minutes. At this point, I am guessing that it will finish ~50 to ~100 project sheets per minute + the time it takes to loop thru PR for each line in MR.

where MR shows employee hours exist
Thank you for that tidbit. Got any more?