# Header [![image.png](https://bookstack.iconography.co.uk/uploads/images/gallery/2025-10/scaled-1680-/Nh8image.png)](https://bookstack.iconography.co.uk/uploads/images/gallery/2025-10/Nh8image.png) Use the Purchase Order header to amend essential information regarding the Purchase Order.
FieldPurpose
Supplier*The Supplier linked to this Purchase Order*

*This field is locked and can not be changed*

Invoice Store*The invoice Store for this Purchase Order*

*On new Purchase Orders, this will default to that set against the Store*

*If additional lines are added through the collation of Purchase Orders, the invoice Store will be updated to match the default of the selling Store; if this has been manually altered, it may need to be reviewed prior to invoicing*

Receiving Store*The receiving Store for this Purchase Order*

*On new Purchase Orders, this will default to that set against the Store*

Supplier Reference*Enter a Supplier Reference number for this Purchase Order*

*This field is optional*

Supplier Instructions*Supplier Instructions are included within the email sent to the Supplier*

*These may be edited and resent to the Supplier using he 'email to supplier' [Action Button](https://bookstack.iconography.co.uk/books/purchase-orders/page/action-buttons "Action Buttons")*

Acknowledged by supplier on...*A label that will show when the Purchase Order was marked as acknowledged*
Date Submitted*The date the Purchase Order was submitted to the Supplier*
Date Due*The date the Purchase Order is due; this is based on the longest Lead Time of any Variant on the Purchase Order*

*This will initially be based on the date the Purchase Order was submitted, and updated once the Purchase Order is acknowledged*

*This will be output in various locations, as the due date for this unit of stock; this is overridden by the Expected Delivery Date*

Expected Delivery Date*A manually entered date*

*This will be output in various locations, as the due date for this unit of stock; this is overridden by the Confirmed Delivery Date (see [Purchase Order Lines](https://bookstack.iconography.co.uk/books/purchase-orders/page/purchase-order-lines "Purchase Order Lines"))*

Delivery Cost*Enter the total cost of delivery*