Invoice all clients at once
Go to: Invoicing → More → Invoice all clients.
Pick the days (last week, last month, the last 2 weeks, or Pick days) and how to group hours. Vaultime lists every client with approved hours not yet invoiced in those days; untick any you don't want. It makes one draft for each client. Nothing is issued: you check each one first.
Example: on the 1st, a cleaning company with 12 clients picks Last month and gets 12 drafts to check and issue.