In practis e in Ax 2009 they were sued for the same thing but there some distinctions to be aware.
Neither goes into stock so neither is part of inventory closing.
You can't issue either a non stock item/or non-stock service to a BOM /formula because it is never received into stock. Non-stock items are meant for trading with direct delivery or for expense items/consumables..
In Ax 2009 items there were no Service items, so the reference data for such a service item was defined specially for these items. In the inventory model group, negative physical and financial inventory were allowed for service items. Furthermore, all ledger integration options, particularly the Post financial inventory for such 'service items' were left blank to ensure that, when we we didn't want to set an item up in Released products because it would not be a recurring purchase, we then purchase by using Procurement category on the PO line and enter the details of the item on Line details - Text.Purchasing e.g.a car service, an expense account was used for receipt transactions. To be able to support non-stocked trade for the sales side, you would instead of defining dummy service items, use the free text invoice function next to the sales order function.
When setting up non-inventoried items, they will have financial dimensions which will carry through to the PO. If you use a procurement category to order on a PO line, you have to manually add the financial dimensions at the line details.
There was a problem with mixing inventory items and non-inventory items on a sales order. You can’t post picking lists for non-inventory items (or non-stocked products in Dynamics AX 2012 terminology), so in the past the process of creating a delivery note or invoice for a mixture of stocked products, and non stock controlled e.g. pallets often required customization.. This problem was resolved in Dynamics AX 2012 with the addition of a parameter to the sales order delivery note/packing slip posting form i.e.:
Dynamics AX2012 useful parameter - "Picked quantity and not stocked products"
This new ‘picked quantity and non stocked products’ option allows to create a delivery note and invoice for a sales order with a mixture of products
It may also be useful for reporting purposes to be able to distinguish more easily between expensed consumables and services.
There also posting differences when you purchase a fixed asset as a stock item or as a non-stock item e.g. you may hold an asset such as a meter inventory until installed or used as a spare part.. You would not buy a fixed asset as a service.
See also: technet.microsoft.com/.../hh803002.aspx
