Valuation and Account Assignment
Valuation areas, valuation classes and automatic account determination
Materials are valued at valuation area level (plant or company code, per customizing). The material's valuation class, combined with the valuation grouping code and the movement's transaction key, drives automatic posting. Core transaction keys: BSX (stock accounts), WRX (GR/IR clearing), PRD (price differences), GBB (offsetting entries for consumption, refined by an account modifier such as VBR, VAX/VAY, AUF), KDM (exchange rate differences), UMB (revaluation).
The valuation class is entered in the material master Accounting view or derived from the material type through the account category reference. Price control decides the valuation logic: S (standard price; differences post to price difference) or V (moving average; recalculated at each receipt and invoice). In S/4HANA the Material Ledger is always active, so materials are valued in multiple currencies/valuation views; actual costing remains optional.
Purchasing account assignment appears on the PO item as the account assignment category (K cost center, F order, P WBS element, and so on) and, indirectly, in the GBB account modifier.
Traps: BSX is the stock account, not GR/IR; a stock-managed PO item ignores account assignment because account assignment applies to consumption; the valuation class in the sales view (used for billing) is not the accounting view class; changing price control from V to S revalues stock and produces a difference posting; the valuation class alone does not determine the account - the valuation grouping code and transaction key do too.
Worked example: standard price 10, PO price 12, GR of 100 pieces. Stock is debited 1,000 (standard price), GR/IR is credited 1,200 and 200 is debited to the price difference account (PRD). At invoice, GR/IR is debited 1,200 and the vendor credited 1,200; stock is not touched again.