Split one invoice across multiple projects

Description:
Each invoice can only be assigned to one project today. When a vendor bills for work on several projects in a single invoice, there’s no way to split that invoice’s amount across those projects the way you can add multiple tags. Splitting a multi-page PDF into separate invoices only helps when each project is on its own page.

What would help:
The ability to assign more than one project to an invoice and split its amount between them, so each project’s budget picks up its share of the cost.

Example:
A vendor sends one invoice covering materials delivered to three job sites. The full amount has to go to a single project, even though the cost belongs to all three.

Submitted on behalf of Kristen Speight, Speight Built.