TECO, mean from PM point of view the order is closed. You cannot change anything , say time or dates in the order. But you can book a invoice say, the order contains a externally procured items.. So you might have done a GR and your PM order work is over.. you can do a Tech and still you can do a MIRO( ie invoice posting )
   
But if you do a Business Closing , you will not be able to do a MIRO.. 
   
Business closing means all the costs are posted and you dont expect any more cost posting. This business closing is a requirment of CO. If you don't do business closing and leave the order at TECH , the cost will recide in the order itself. As per the settlement rule , the cost should get transfer to the cost centre you have defined. But in TECH stage the cost is still in Order. Once you do a KO88 and then a business closing, the cost get transferred to a cost centre..

You need to make sure that all financial postings hav ben completed before doing a business completion.

You can use transaction CO99 to Business Complete your orders. Using this transaction allows you to select the number of days an order has been TECO'd before you business complete it. E.g if you are confident that all financial postings will be complete within 60 days, you cal select 60 days as the retention period. This means that orders have to be TECO'd for a period of 60 days before the system will select them for completion.

Batch completion PM orders is done with transaction CO99.
As a consequence, orders are completed if:
- Not yet administrative completed
- Technical completed longer than “a number of  days” ago
- No open liabilities (open purchase orders – not yet invoiced purchase orders)

In our company we do Order closing in the following way:

1. IW41 - Complete confirmation
2. IW32 - Technical completion & Business completion
3. KO88 - Cost Settlement

Tips by : Debajit, Dougie

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