When a user enters an expense, it goes to the manager for approval. Looking into the expense, the manager may approve or reject the expense entry. If the expense entry is approved, it is added to the project cost/bill amount but if it is rejected, it goes back to the user. The user can edit it, and send it again for the manager's approval or delete it and fill a new expense entry.

Celoxis provides a basic workflow from the time an expense is submitted for approval to it is approved.

Pending Approval - When a resource submits an expense against the task for approval to the PM. The Project Manager is notified via email whenever an expense is submitted. Only a user with 'Approve' expense privilege can approve the expenses. The user who submitted the expense cannot edit the expense any more after submitting it. Only the user who has 'Edit' permissions can edit the expense.
Approved - The Project Manager or the user with Approve privileges can approve the expenses. The Cost (Actual) and/or Amount (Act, Billable) of the task and the project is affected after the expense is approved. The submitter receives a notification that the expense has been approved. Only the user with appropriate privileges (Edit + Approve) can edit the approved expenses.
Rejected - The Project Manager or the user with Approve privileges can reject the expenses. The submitter receives a notification that the expense has been rejected. The user who submitted the expense can now edit the expense and resend it for approval.
Invoiced (since V6.5) - Expenses that are billable and approved can be marked as invoiced to indicate that the client has been invoiced this amount. Invoice is a separate privilege that needs to be granted. Invoiced entries are shown in green.

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