Scenario 26 — MM ↔ PS Integration (Project-Based Procurement / WBS)
📊 Business Case
This scenario is where MM hands off to Project System (PS) for capital projects. A big capex job — building a new plant extension — is structured in PS as a Work Breakdown Structure (WBS): a tree of project phases. Every purchase (steel, equipment, concrete) is tagged to a specific WBS element with account assignment P (Project), so the cost rolls up to the project instead of hitting a cost center or inventory. At completion, the accumulated cost settles through an Asset Under Construction (AuC) to the final fixed asset. It shows MM enabling long-running capex across the SAP suite.
🕐 When to use it
For any project-based or capex procurement — plant builds, expansions, large installations — where cost must be tracked per project phase and ultimately capitalized as an asset.
❓ Why it matters
It teaches account assignment P and WBS-based cost accumulation — different from a cost center. The project (not stock) carries the cost, enabling accurate capex tracking and the AuC → final-asset chain.
👤 Who triggers it
The PS consultant builds the project/WBS; the MM buyer raises POs tagged to a WBS element and handles GR/IV; PS/CO settles the WBS to AuC (CJ88) and on to the final asset.
🔁 The key distinction
Cost rolls up to the project, not inventory. With account assignment P the spend lands on the WBS element and is visible in the project cost report, then capitalizes via AuC — never sits as stock.
💰 Financial Impact — The Easy-Money Example
PakSteel buys 100 TO of structural steel beams (PKR 80,000/TO = PKR 8,000,000) for the galvanizing plant build. The PO carries account assignment P against WBS element GALV-001-CONST, so the money rolls up the project tree toward a fixed asset — never into inventory:
The big idea: account assignment P means project spend is never inventory — it is charged to the WBS element at GR and rolls up the project. CJ88 then settles the WBS to an Asset Under Construction, and at go-live the AuC becomes the final depreciating asset. The project, not stock, holds the capex until it is capitalized.
🇵🇰 The Business Story
🎯 What you'll learn
- Account assignment
P(Project / WBS) on the PO line - WBS-based cost accumulation (different from cost center)
- Asset Under Construction (AuC) handling for capex projects
- Multi-step settlement: WBS → AuC → Final Asset
- How MM enables long-running capex projects in SAP
⚙️ Prerequisite Setup
- Skip this scenario (PS is specialized — many companies don't use it)
- Substitute with Scenario 6 (Asset Procurement direct, account assignment A) — simpler, similar MM mechanics
- OR work with a PS consultant to create a basic project + WBS for testing
Goods Receipt · Reference Purchase Order → mvt 101 (the account-assigned P PO — cost goes to the WBS element, not stock). Full guide: MIGO Selection Bar.
- The Project System (PS) module and FI-AA active, with a released project + at least one WBS element — e.g. GALV-001-CONST (see the Prerequisite Setup note above).
- A controlling area set up so the WBS can collect and settle cost (see Setup Step 19).
- A vendor to buy the beams from (see BP Create Guide).
🔧 Step-by-Step — Transaction Flow
| Step | T-code | What it does | Why this step exists |
|---|---|---|---|
| 26.1 | CJ20N | Build and release the project tree with WBS phase boxes | Project costs need boxes to collect in |
| 26.2 | ME21N (acct P) | Create the PO tagged P + WBS, so cost hits the project | A promise needs a document — routed to the project |
| 26.3 | MIGO 101 + MIRO | Receive the beams and record the bill — cost lands on the WBS, no stock | Goods and bill must be recorded before paying |
| 26.4 | CJ88 | Settle the collected WBS cost to the Asset Under Construction | Project cost must become an asset, not stay parked |
| 26.5 | F-53 | Pay the vendor — payable cleared, bank goes down | A purchase isn't finished until the vendor is paid |
26.1 — PS Project + WBS · CJ20N
⚡ This step will: build and release the project tree — a live project with WBS phase boxes now exists, ready to collect every cost the POs will charge to it. 📄 paper: — (project + WBS master data) · 📦 stock: no change · 💰 money: no posting
PS consultant creates the project structure (typically before MM gets involved). The CJ20N Project Builder screen has three areas: the structure tree (top-left — the project definition and its WBS hierarchy), the worklist (bottom-left — recently used projects/templates), and the work area (right — the detail of whatever object you select in the tree). You build the tree on the left and fill each element's fields on the right.
| Where on screen · Field | Fill | What the field asks (plain words) | Why we choose this — and the impact if wrong |
|---|---|---|---|
| Structure tree · Project Definition | GALVAN-PRJ-001 "Galvanizing Plant Extension" | What is the WHOLE job? The project definition is the trunk of the tree — the one name the entire capex build lives under. | A single project definition ties every phase and cost together into one reportable capex job. Impact: no clear project definition and costs cannot roll up into one project |
| Structure tree · WBS elements (the branches) | GALV-001-CONST · GALV-001-EQUIP · GALV-001-INST | What are the PHASES of the job? A WBS (Work Breakdown Structure) splits the project into pieces — like folders inside one big project folder. | Each element is its own cost box, so you later see spend per phase (Construction, Equipment, Installation), not one lump. Impact: too few elements and you lose phase-level cost visibility and budget control |
| Work area (WBS detail) · Cost element | (per WBS) | Which kind of cost may this phase collect? The "type of money" the box accepts. | It lets the WBS receive the procurement expense at goods receipt. Impact: a missing or blocked cost element and postings to the WBS are rejected |
| Work area (WBS detail) · Account-assignment setting | (per WBS) | Is the phase allowed to be charged directly — can a PO post to it? | Set so a PO line can name this WBS and charge it. Impact: wrong settings here and the ME21N account assignment P (26.2) cannot post to the element |
| Work area (WBS detail) · Settlement rule | (per WBS) → to AuC asset | Where does this phase pass its collected cost on to? | The rule points at the AuC (Asset Under Construction) — the half-built asset the costs gather into before becoming a final asset. Impact: no settlement rule and CJ88 (26.4) has nowhere to move the cost, so it is stranded on the WBS |
| Toolbar · Save + release the project | — | Is the project open for business yet? Releasing switches it from draft to live — like opening a shop. | Only a released project lets work and costs be booked against its WBS elements. Impact: leave it in draft and POs cannot post to the WBS — procurement is blocked before it starts |
26.2 — Create PO with WBS Account Assignment · ME21N with acct P
⚡ This step will: turn the project's need into a binding promise to the vendor — the PO line carries P + the WBS element, so at GR the cost will land on the project, not in stock. 📄 paper: purchase order · 📦 stock: no change · 💰 money: no posting
Same ME21N 3 zones — Header (supplier at top), Item overview grid (the beam line + the AcctAssCat column A), Item detail tabs (the Account Assignment tab carries the WBS element and G/L). Fill the AcctAssCat column first so the WBS field opens in the detail tab.
| Where on screen · Field | Fill | What the field asks (plain words) | Why we choose this — and the impact if wrong |
|---|---|---|---|
| Header (top) · Vendor | Pak Steel Structures (or any vendor) | WHO supplies the goods? The normal start of any PO. | The supplier the beams are bought from. Impact: the wrong vendor orders from and pays the wrong company |
| Item grid · Material | "Structural Steel Beam I-200" | WHAT are you buying? | The beams for the plant build. Impact: a wrong material orders the wrong goods for the project |
| Item grid · Quantity | 100 TO | HOW MUCH — in what unit (TO = metric tonnes)? | 100 TO is what this phase needs; 100 × 80,000 = the PKR 8,000,000 in the story. Impact: a wrong quantity mis-states the project spend |
| Item grid · Net Price | 80,000 PKR/TO | The unit price of the beams. | Sets the value that rolls up to the WBS. Impact: a wrong price misstates the capitalised project cost |
| Item grid · AcctAssCat column (A) | P (Project) | WHERE should this cost land? Like writing on the receipt whose budget it belongs to. P = charge it to a project (WBS element); blank = goods go into stock; a cost centre = a department's running cost. | Capex beams belong to the project, so P routes the cost to the WBS to be capitalised — not into stock. Impact: leave it blank and the beams post to inventory as ordinary stock, so the project shows no cost and capex tracking breaks |
| Item detail → Account Assignment tab · WBS Element | GALV-001-CONST | WHICH phase of the project pays? | Picks the exact branch (Construction) from 26.1, so the beams' cost rolls up under that phase for phase-level visibility. Impact: a wrong WBS charges the wrong phase, distorting per-phase budgets |
| Item detail → Account Assignment tab · G/L Account | auto-determined (project consumables) | Which expense bucket in the books? Usually auto-filled from the P assignment. | It is an expense account, not inventory, because the spend belongs to the project rather than stock. Impact: forcing an inventory G/L contradicts the P logic and the posting is rejected or mis-states the books |
| Toolbar · Save | → PO # | Commits the PO. | PO ready; at GR the cost flows to the WBS element, not a cost centre. Impact: unsaved, there is no PO for the GR (26.3) to receive against |
Result: When GR happens, cost goes to WBS GALV-001-CONST, not a cost center.
26.3 — GR + MIRO — Standard, but cost tags to WBS · MIGO mvt 101
⚡ This step will: bring the beams in and record the bill — but no shelf fills: the cost lands straight on WBS GALV-001-CONST, and MIRO then turns the GR/IR IOU into a real debt to the vendor. 📄 paper: material + accounting document, then invoice document · 📦 stock: no change (acct P — goods never become stock) · 💰 money: GR: Dr Project Expense (WBS) / Cr GR/IR · MIRO: Dr GR/IR / Cr Vendor
Do (GR): MIGO → Goods Receipt + Purchase Order → type the acct-P PO → Enter → tick Item OK → Post. (See the MIGO top-bar note above the steps.)
| Where on screen · Field / Action | Fill | What it asks (plain words) | Why — and the impact if wrong |
|---|---|---|---|
| Top bar (header line) · Action + Reference | Goods Receipt + Purchase Order → the PO no. | What are you doing, against which paper? Receiving the beams, against their PO. | The PO carries account assignment P and WBS GALV-001-CONST with it. Impact: no PO reference and the cost has no WBS to roll up to. |
| Top bar (top-right) · Movement Type | 101 (auto) | Which kind of movement is this? | 101 = goods receipt for a PO — proposed automatically. Leave it. |
| Item detail → Where tab · Storage Location | field is ABSENT / greyed — correct! | Where should the beams be put in stock? | Account assignment P means they are NOT stocked — the cost goes to the project — so SAP does not even ask for a location. Impact: if this field DID appear and demand a value, the line had lost its P assignment and would wrongly post to stock. |
| Item detail → Account Assignment tab | shows the project G/L + WBS GALV-001-CONST, read-only | Where will the cost land? | Decided on the PO (26.2); MIGO only executes it. Check it reads right before posting. |
| Item overview grid · ☑ Item OK → toolbar · Post | tick the line → Post → note the material doc | Confirm the line, then make it real. | Forget the tick and Post fails "no items selected" — the #1 MIGO beginner error. |
What changes at this exact moment (the posting for this scenario):
| Project Construction Expense (4500xx) | Dr 8,000,000 | WBS: GALV-001-CONST |
| GR/IR (191100) | Cr 8,000,000 | — |
Then MIRO (the vendor's bill): Dr GR/IR 191100 · 8,000,000 (the tray is emptied) / Cr Vendor · 8,000,000 (now a payable). The beams' cost is not touched again — it already rolled onto the WBS at GR.
The difference from a stock GR: a normal 101 debits inventory; here the same 101 debits Project Construction Expense tagged to WBS GALV-001-CONST — no stock line at all. The WBS now shows PKR 8,000,000 in the project cost report, waiting to settle (26.4).
26.4 — Settle WBS → Asset Under Construction (AuC) · CJ88
Periodically (monthly during project), PS/CO consultant settles WBS cost to AuC. 📄 paper: settlement document · 📦 stock: no change · 💰 money: Dr AuC / Cr WBS GALV-001-CONST
At project completion, AuC settles to final operational asset via AIBU.
Asks: where does the piled-up project cost go now? "Settle" = move the collected cost onward. During the build it moves each month from the WBS into the AuC (Asset Under Construction) — an asset that is still being built, so it does not depreciate yet. When the plant is finished, AIBU settles the AuC to the final operational asset, which then starts to depreciate. The chain is WBS → AuC → Final Asset — the whole point of tagging every PO with P.
What changes at this exact moment (CJ88, run monthly):
| Asset Under Construction (AuC) | Dr 8,000,000 | the half-built asset now carries the cost (it does not depreciate yet) |
| WBS GALV-001-CONST | Cr 8,000,000 | the project box is emptied of this cost — its balance drops back |
The chain made concrete: CJ88 moves the WBS cost to the AuC every month while building; at go-live AIBU moves the AuC to the final operational asset, which then starts to depreciate. WBS → AuC → Final Asset — the whole reason every PO was tagged with account assignment P.
26.5 — Pay the vendor · F-53 (closes the money loop)
⚡ This step will: pay the debt: the vendor's account clears and the bank shrinks. 📄 paper: payment document · 📦 stock: no change · 💰 money: Dr Vendor / Cr Bank
The MIRO in 26.3 created a real payable to the beam supplier (Cr Vendor 8,000,000). CJ88 (26.4) only moved the cost internally toward the asset — it did not pay anyone. The cash still has to leave the bank, and that is this step.
Do: F-53 → header → Bank data → Process Open Items → balance 0.00 → Post. Same manual outgoing payment as Scenario 1, Step 5.
| Where on screen · Field | Fill | What it asks (plain words) | Why — and the impact if wrong |
|---|---|---|---|
| Header · Document / Posting Date | today | When did the payment happen / in which period does it post? | Same-day defaults are right. Impact: a date in a closed period is rejected. |
| Header · Company Code | PSPK | From WHOSE books does the cash leave? | PSPK is the company running the capex project and owing the supplier. Impact: the wrong company code pays from the wrong books. |
| Header · Currency | PKR | In WHICH money do you pay? | The payable is held in PKR, so pay in PKR. Impact: a wrong currency mis-converts the amount. |
| Bank data · Account (G/L) | 113100 | From WHICH bank account does the money go out? A G/L account = one line in the books. | 113100 is the Bank Main Account — the same one Scenario 1 paid from. Impact: a wrong G/L drains the wrong bank ledger. |
| Bank data · Amount | 8,000,000 | HOW MUCH leaves the bank? | Matches the vendor payable from the 26.3 MIRO (100 TO × ₨80,000). Impact: pay less and part stays open; more and the supplier is over-paid. |
| Open item selection · Account (Vendor) | Pak Steel Structures (from 26.2) | WHOSE bill are you paying? | The beam supplier whose payable you are clearing. Impact: the wrong vendor shows no matching open item. |
| Process Open Items · select the invoice | Amount Entered = Assigned · balance 0.00 🟢 | Which exact open item does this cash clear? | Ticking the 26.3 invoice ties the cash to the debt so the vendor nets to zero. Impact: if "Not assigned" ≠ 0, SAP will not let you Post. |
| Toolbar · Post | note the payment document number | Make the payment real? | Post writes the cash-out and clears the payable. Impact: until you Post, the supplier stays open. |
What changes at this exact moment:
| Trade Payables — Pak Steel Structures (via recon 160000) | Dr 8,000,000 | the payable the 26.3 MIRO created is cleared |
| Bank Main Account (113100) | Cr 8,000,000 | cash leaves the bank — the supplier is square |
It is easy to think CJ88 "finished" the project buy — it did not. CJ88 moves cost (WBS → AuC → asset) so the balance sheet shows the right asset; F-53 moves cash (bank → vendor) so the supplier is actually paid. One is a CO / asset thread, the other is the ordinary AP thread. Account assignment P changed where the cost lands, but paying the vendor is identical to Scenario 1: debit the payable, credit the bank.
Verify: FBL1N → Pak Steel Structures → "Open items" empty; invoice + payment share one Clearing Document. FBL3N → G/L 113100 shows the ₨8,000,000 cash-out.
- Configure your PO doc types to ALLOW account assignment P
- Create custom PO doc type for capex projects (ZCAP) — see Scenario 20
- Ensure release strategy triggers Director/Board approval for PS-tagged POs
- Coordinate with the PS team on planned vs actual procurement timelines
- Handle change orders to project-specific contracts
✅ Verification
| # | T-code | Check |
|---|---|---|
| 1 | CJ20N / CN41 | Project GALVAN-PRJ-001 released with WBS elements GALV-001-CONST/EQUIP/INST |
| 2 | ME23N | PO line has Account Assignment Category P with WBS Element GALV-001-CONST |
| 3 | FB03 / MB03 | GR document: Project Construction Expense (4500xx) Dr / GR-IR Cr — no inventory (300xxx) line |
| 4 | S_ALR_87013542 / CJI3 | WBS GALV-001-CONST shows the 8,000,000 actual cost in the project cost report |
| 5 | AW01N | After CJ88, the Asset Under Construction carries the settled project cost |
🎓 Interview-Ready Answers
Q: What does account assignment category P mean, and how is it different from a cost center?
P = project — the procured item is charged to a WBS element rather than received into stock or charged to a cost center. At GR there is no inventory posting; the cost lands on the WBS and rolls up the project tree. A cost center (account assignment K) collects period/department cost; a WBS collects project cost across phases and ultimately capitalizes it as an asset.
Q: Walk me through how project procurement cost becomes a fixed asset.
POs tagged to WBS elements post their GR cost to those WBS elements (e.g. 4500xx Dr / GR-IR Cr). The WBS accumulates all project spend. Periodically CJ88 settles the WBS to an Asset Under Construction (AuC). At project completion the AuC is settled to the final operational asset (via AIBU), which then depreciates. So the chain is WBS → AuC → Final Asset.
Q: What is a WBS element and why structure a project that way?
A Work Breakdown Structure decomposes a project into hierarchical elements (phases like Construction, Equipment, Installation). Each WBS element is a cost collector with its own budget, account assignment and settlement rule. Tagging each PO to the right WBS gives phase-level cost visibility, budget control, and clean settlement to AuC — far better than dumping all capex on one cost center.
Q: What is the MM consultant responsible for in this PS scenario?
Not PS config. MM ensures the PO document types allow account assignment P, often creates a dedicated capex PO doc type (ZCAP), sets the release strategy so project POs route to Director/Board approval, coordinates planned-vs-actual procurement timing with PS, and handles GR/IV and change orders for project contracts. MM enables the buy; PS, CO and Asset Accounting own the capitalization.