You can enable the ability to apply an invoice to a budget. Go to Business > Settings > Budgets and see these settings:
Firstly enable the feature.
You can have an option to either just adjust a budget with the invoice that’s created or create a retrospective purchase as well.
If you enable the workflow step, you will be able to create a new workflow step of “Apply to Budget”.
With the settings above set to suit, record an invoice. If the invoice relates to a Division with a budget (nominal or cost code) or a Project with a budget,
You will see the “Apply to Budget” section as shown above.
The choice you have here is to apply this on “Creating of the invoice” or if the invoice is approved, as part of a workflow.
The latter would require you to place the “Apply to Budget” workflow step in your invoice approval workflow.