Questions: Tell me the difference between transfer postings and stock transfers.  What are the material documents that are generated and what are the accounts hits.

Stock Transfer = physically stock transfer of goods,
Trasfer posting = may physical (or) logical (not physical) stock transfer of goods.

Transfer posting and stock transfer:
Transfer posting : plant to plant/ Storage location to Storage Location.
In which if the valuation area is same. i.e. 
- Sloc to Sloc within one plant then there will be no accounting entry occurs. 
- However if the its Sloc to Sloc but with two different plant. and valuation area+valuation price is diff then there will accounting doc and material doc created for the same. 

Stock Transfer:
There are unrestricted stock, quality inspection stock, blocked stock.   Also you can have GR Blocked stock, special stock too.  It will update the quantity.                                            *-- Madhura k

Stock Tranfer and Transfer Posting - Importances are same up to Plant to Plant . However Customer ( Client ) Prefer Stock Transfer than Transfer Posting. 

See the Below Advantages of Stock Transfer more than Transfer Postings :
The transfer of stock using a stock transport order has the following advantages over the transfer of stock without a stock transport order:
- A goods receipt can be planned in the receiving plant. 
- You can enter a vendor (transport vendor) in the stock transport order. 
- Delivery costs can be entered in the stock transport order. 
- The stock transfer order is part of MRP: Purchase requisitions that were created in MRP can be converted into stock transport orders. 
- The goods issue can be entered using a delivery via Shipping (LE-SHP 
- The goods receipt can be posted directly to consumption. 
- The entire process can be monitored via the purchase order history. 
However we need to do some times Plant to Plant Trasfer Postings only in some industires. This is based on Customer Requirement.                                                                       *-- Pavan G Kulkarni

How many stock transfer  process are avaikable in SAP? 
Like  1)Two step  stock transfer (MM/SD) .
          2)Two steap stock transfer ( MM only)  Move type 303&  305.
          3) One step stock transfer  Move type 301.

Stock Transport Order (STO)

Without STO 
One step stock transfer Move type 301.
Two step stock transfer ( MM only) Move type 303& 305.

Using STO without delivery: 
  doc.type: UB
  GI:351, GR:101
 
  STO with delivery:
  GI:641, GR:101
  delivery type:NL
 
  STO with delivery and billing:
  GI:643, GR:101
  delivery type:NLCC , billing type:IV                               *-- Gaurav

Related:

• SAP Material Management Interview Questions
• SAP MM Support Problem Solution

SAP Material Management Books
SAP MM Books - Certification, Interview Questions and Configuration

SAP Materials Management Tips
SAP MM Configuration Tips and Materials Management Discussion Forum

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