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The Sign-Off Table

Lesson 2 of 6

Sourcing and conversion to purchase orders

9 min

A requisition becomes useful when it has a source of supply and is converted to a purchase order. At Contoso, MRP creates hundreds of rotor requisitions a month, while self-service creates a steady trickle of one-off requests. The first group should flow to POs with almost no touch; the second needs a buyer.

Assigning a source

A requisition item can get its source in several ways: MRP assigns one from an MRP-relevant source list entry or quota arrangement; the requester picks a catalog item that already carries supplier and price; or a buyer assigns one. Buyers use ME57 (assign and process requisitions) or the Fiori requisition apps for purchasers, such as Manage Purchase Requisitions - Professional. Source determination proposes valid info records, contracts and source list entries.

  1. Open requisitionsBuyer lists approved, unassigned requisitions for purchasing group 001
  2. Source proposalSAP proposes Lakeside Components from the source list and contract
  3. AssignBuyer accepts or picks another valid source
  4. ConvertAssigned requisitions are grouped and converted into POs
  5. ResultOne PO per supplier and purchasing org, items linked to their requisitions
Manual source assignment and conversion by a buyer.
The Sign-Off Table · thesignofftable.com/academy/sap-mm-202

Automatic conversion

For repetitive purchases, Contoso lets the system create POs from requisitions in a scheduled job, using ME59N (automatic creation of POs from requisitions) or the equivalent Fiori scheduling. Automatic conversion only picks up requisitions that meet all the conditions.

  1. The requisition is approved (released), if an approval applies.
  2. A source of supply is assigned (supplier with info record, or contract).
  3. The automatic PO indicator is set on the product's purchasing view.
  4. The automatic PO indicator is set on the supplier's purchasing org data.
  5. The requisition is not blocked or already fully ordered.
  1. Is the requisition approved?Yes → next check · No → waits for approval
  2. Does it have an assigned source?Yes → next check · No → buyer must assign one
  3. Are auto PO flags set on product and supplier?Yes → next check · No → buyer converts manually
  4. Did the scheduled job run with matching selection?Yes → PO created · No → check job selection and log
Why a requisition was or was not converted automatically.
The Sign-Off Table · thesignofftable.com/academy/sap-mm-202

How requisitions are grouped into POs

Conversion groups requisition items into POs by supplier, purchasing organization, and other split criteria the job or user chooses (for example, plant or delivery date). Twenty rotor requisitions for Lakeside in plant 1710 can become one PO with twenty items, or twenty POs, depending on the settings. Fewer POs means fewer outputs to Lakeside and easier invoice matching, so agree the grouping rules with the supplier and accounts payable.

Low volume, standardBuyer converts in batches weekly
High volume, standardAutomatic conversion job; buyer handles exceptions
Low volume, one-offBuyer sources and converts each one
High volume, one-offCatalogs and contracts to turn one-offs into standard items
Choosing manual or automatic conversion by demand pattern.
The Sign-Off Table · thesignofftable.com/academy/sap-mm-202

What would you do?

Rotor requisitions with Lakeside assigned are approved, but the nightly job never converts them. The job log says "no automatic PO allowed." What do you check?

Buyers who process requisitions in the Fiori apps see them as a work list with filters for purchasing group, plant and source status. Items with a single valid source can be converted in one step; items with several sources show the options with price and validity. Public Edition customers work only in these apps; Private Edition and on-premise users can mix them with ME57 and ME59N. Whichever tool you use, the outcome to test is the same: the right requisitions become POs with the right supplier, and the rest are visible to a buyer.

Key points
  • Requisitions get sources from MRP, catalogs, or buyers using source determination.
  • Buyers assign and convert with ME57 or the Fiori requisition apps.
  • Automatic conversion (ME59N) needs approval, an assigned source and auto PO flags on product and supplier.
  • Grouping rules decide how many POs result; check the job log as evidence.

Check your understanding · not graded

Lesson check

  1. 1. Which transaction creates POs automatically from requisitions?

  2. 2. Which of these is a precondition for automatic conversion?

  3. 3. Which transaction lets a buyer assign sources and process requisitions?

  4. 4. What decides how many POs result from a set of requisitions?