Hi guys... Is it possible to sum a sublist column value inside a workflow? Without using a script.

Yes...kind of. You would just need to make a custom field sourced by a Saved Search on the record/transaction, then you can use that custom field in your workflow

Or you could add a "workflow" custom field and create a sublist group that loops through the sublist and adds to the workflow field. Then you could use the workflow field

But wouldn't that only work on "Items" sublists? I think that's the only sublist exposed in Workflows. Strangely, I was just starting a similar project yesterday afternoon, but it's a custom record/sublist which I can't get to in the workflow itself - but I like the saved search idea.

Yes @Mark C only the Items sublist is available to workflows at this time

Thanks @AI1 @Jordan Brandley @Mark C