Can you set a formula in QB online to incorporate overhead costs within project reports?

Thanks for checking this feature with us, @FMC UK,

At the moment, we're unable to assign formulas on reports for overhead costs. To track these expenses, you can create transactions like Bills or Expenses within the Projects page. This way when pulling up related reports, overhead costs will show as expenditures.

See the following snapshots:

You can also see the following articles to learn more about tracking overhead expenses on Projects:

• NEW for QuickBooks Online: Labor Costing for Projects!
• How To Calculate And Track Overhead Costs

Let me know if there's anything else I can do to help you. I'm just a click away if you need further assistance. Have a nice day!