ME57 — Assign and Process Purchase Requisitions
ME57 lets a buyer work a worklist of purchase requisition items that still need a source of supply, assign a vendor from an info record, contract, scheduling agreement or source list, and then trigger the follow-on RFQ or purchase order directly from the same screen, rather than doing assignment and document creation in two separate transactions.
This page covers ME57, the transaction that combines source-of-supply assignment with follow-on document creation for purchase requisitions. It focuses on why requisitions disappear from or never appear on the ME57 list, why source assignment fails, and why buyers occasionally generate duplicate purchase orders from the same requisition line.
Reviewed by an ERPClimb SAP consultant on 15 Sept 2026· 1,055 words
Purpose
ME57 pulls a list of purchase requisition items and lets the buyer assign a source of supply to each one, then immediately convert the assigned line into a request for quotation or a purchase order. The structural fact that explains most confusion is that ME57 is not a passive list report like ME5A - it is a working transaction that writes documents. Selecting 'assigned' versus 'still to be assigned' on the selection screen changes what appears, and processing a line here can create a PO or RFQ in the same step as the assignment, with no separate confirmation screen distinguishing the two actions clearly to a first-time user.
When it is used
ME57 is reached for when a requisition has cleared release (if release strategy applies) but has no fixed source and needs manual vendor selection - typically direct material or services requisitions without a maintained source list entry. It sits between requisition creation/release and PO issue. Buyers use ME58 instead when the source is already assigned and only document creation is needed, and ME59N when the whole assignment-to-PO chain should run in background without manual intervention. The Fiori app for managing purchase requisitions covers the same ground with a worklist UI, but ME57 remains common for batch processing by experienced buyers.
How to use it in practice
- Call ME57 and set the selection screen: plant, purchasing group, material group, requisition number or date range
- Choose whether to list requisitions still to be assigned, already assigned, or both
- Execute the list; each line shows the requisition item and any proposed source
- Select a line and either accept the proposed source or open source assignment to pick a vendor from info record, contract, scheduling agreement or source list
- Mark the processed lines and trigger 'Assign and process' to generate the RFQ or PO
- Save; check the message log for lines that could not be converted
Key data objects
- EBAN - the purchase requisition item itself, including quantity ordered so far, release indicator and deletion flag, which determine whether a line is eligible for processing
- EKKO and EKPO - header and item of the purchase order (or the RFQ header/item equivalent) created as the follow-on document
- EORD - source list entries that ME57 reads when proposing a vendor
- EINA and EINE - general and plant-specific purchasing info record data used to derive price and default vendor for the proposal
How to prove it in the data
In SE16 on EBAN, filter on the requisition document type and purchasing group, then compare BSMNG (quantity already ordered) against MENGE (requisition quantity) to see whether a line is fully, partially or not yet converted. Check FRGKZ for release status and LOEKZ for a deletion flag that silently removes lines from the ME57 list. Take the requisition number and item from a line of interest and look it up in EKPO via the BANFN and BNFPO fields to find the resulting purchase order, or confirm none exists if conversion failed.
ECC vs S/4HANA
ME57 behaves the same functionally on S/4HANA; the underlying requisition and purchasing document tables are unchanged in structure for this purpose. The Fiori app for managing purchase requisitions offers an equivalent worklist-driven experience with source assignment built into the item detail, and is the preferred entry point for casual or occasional buyers, but ME57 continues to work and is still favored for bulk processing by purchasing teams already trained on it.
Common pitfalls and how to diagnose them
- Line missing from the list: the requisition has not cleared its release strategy, so FRGKZ in EBAN does not show it as released, or the line already has BSMNG equal to MENGE meaning it is fully ordered and correctly excluded, or a deletion flag was set (LOEKZ) which removes it from any further processing.
- No source proposed: there is no valid info record, contract or scheduling agreement covering the material, plant and vendor combination in the requisition's validity window, or a source list entry exists but is marked with the fixed-vendor indicator pointing to a different vendor than expected, which silently blocks manual override unless the indicator is checked first.
- Duplicate purchase order created: the same requisition line was processed twice, usually because a first ME57 run failed partway through document creation and the requisition quantity was not fully consumed, or two buyers worked the same worklist concurrently without refreshing between runs. Check EKPO for more than one PO item referencing the same BANFN/BNFPO before assuming the requisition itself is corrupt.
- Wrong document type generated: the processing option on the selection or assignment screen defaulted to RFQ creation instead of PO, or vice versa, because the buyer accepted a default rather than explicitly choosing the target document category.
- Partial quantity stuck open: a buyer split the requisition quantity across sources and only processed part of it, leaving an open balance that reappears on every subsequent ME57 run and looks like a data error when it is simply an unfinished split assignment.
Whose problem this is
This is a functional MM/purchasing issue in almost all cases - release strategy configuration, source list and info record maintenance, and purchasing group setup are all functional territory. ABAP involvement is only needed if a custom source determination BAdI or enhancement is altering the standard proposal logic. A good handover states the requisition number, item, current BSMNG/MENGE values, and whether a source was expected to exist.
Related SAP objects
Reviewed pages this object connects to in the ERPClimb knowledge graph.
Source: ERPClimb — https://erpclimb.com/sap-tcodes/me57ERPClimb is an independent platform and is not affiliated with SAP SE. Reference pages are written and reviewed by SAP consultants for learning and troubleshooting.