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The Contract field is filled automatically for the selected company with the default contract. If necessary, you can change it by selecting the contract from the Company Contracts list (to open the list, select Show all in the drop-down list).
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The Project field is available if the Project Costing functionality is turned on on the Administration > Settings > Project Costing form. You can link the invoice with a project from the list of available projects. If the items in this invoice are associated with different projects and you need to specify different projects for different items, you can move the Project field from the Main tab as a column to the table on the Inventory and Services tab. For this, use the Settings button on the toolbar (for more information, see Document Toolbar).
If the Enable Project Tasks option is selected on the Administration > Settings > Project Costing form, you can link the entire document with a specific project task or document's line items with multiple project tasks. By default, the Project Task column is available on the Inventory and Services tab. If needed, you can move it as a field to the Main tab. For this, use the Settings button on the toolbar.
The Order field is filled in automatically if the invoice is based on the customer order. You can link the invoice to a customer order manually; for this, click the arrow button in the field, then click Show all. The list of customer orders appears; only the orders for the same contract are shown in the list. If you need to copy the details from the order to this invoice, click the Fill by Order ( 
) button to the right in the field.
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