¶ Credit Note
At a Glance
Owner: Procurement / AP · Table:tb_credit_note(+ detail, comments) · Workflow: reuses PO-side definition · Upstream: good-receive-note · Post-receipt offset against a prior GRN — reverses AP and either returns goods or revalues cost.
¶ 1. What & Who
A Credit Note (CRN) is the post-receipt correction instrument in procure-to-pay. When a vendor over-bills, ships defective or short goods, or grants a retrospective rebate, the CRN documents the offset against the originating GRN and reverses the AP liability. Two variants: quantity_return physically returns goods (decrements stock, reverses the cost layer) and amount_discount is a pure price correction (no inventory movement, revalues lot cost).
Created by Procurement when the vendor issues a credit invoice · Approved by workflow approvers (PO-style routing) · Read by AP (debit-memo source) and the costing engine.
¶ 2. Common Tasks
| Task | Where | Notes |
|---|---|---|
| Raise a CN against a GRN | Procurement → Credit Note → New | Pick the GRN; lines pre-fill from receipted quantities |
Pick quantity_return vs amount_discount |
Header credit_note_type |
Return moves stock; discount only revalues cost |
| Set return-to-stock vs write-off | (Automatic) | Engine returns to the original FIFO lot; if lot is consumed, posts variance to write-off GL — see costing COST_XMOD_006 |
| Apply CN to AP | Completes on doc_status = completed |
Always emits an AP debit memo (base_total_price) |
| Cite vendor's credit-invoice ref | Header invoice_no / tax_invoice_no |
Required for AP three-way match |
| Void a posted CN | Detail → Void | Only while the posting period is open; reverses every posting |
¶ 3. Validation & Errors
| Symptom / Message | Cause | Action |
|---|---|---|
| "GRN required for quantity_return" | Type is quantity_return but grn_id empty |
Pick the anchor GRN |
| "Return qty exceeds receipted - already returned" | Cumulative returns would over-deplete the lot | Reduce qty or split across multiple lots |
| "Tax rate must match GRN snapshot" | is_tax_adjustment = true was expected for retrospective tax |
Toggle is_tax_adjustment on the line |
| "Period is closed — cannot void" | Posting period for the CRN has closed | Raise a corrective journal voucher instead |
| "Rate not in history" | No tb_exchange_rate row on cn_date for that currency |
Add a rate then re-open the CRN (see master-data/exchange-rate) |
| "User not authorised at this stage" | Signed-in user not in user_action.execute[] |
Wait for the correct approver, or escalate |
¶ 4. Edge Cases
- Money rounding. Line money fields stored at
Decimal(20,5); computed totals round half-up to 2 decimals at line level, then sum into header (matches PO/GRN rounding). - FX revaluation. When
cn_date != grn_dateand currencies differ from BU base, engine resolves a fresh rate oncn_dateand posts the delta to FX gain/loss per costingCOST_CALC_005. - Return-to-stock vs write-off.
quantity_returnreverses the FIFO lot if it still exists; if the lot is already consumed (issued via SR / stock-out), the variance lands on a configured inventory write-off GL account (no negative inventory). - Snapshot semantics. Vendor name, product, currency, FX rate, tax rate, and pricelist refs are snapshotted at draft. Master-record edits do NOT retroactively change the CRN.
- Voiding window. A
completedCRN may only be voided while its period is open. Oncetb_period.status = closed, voiding is rejected. - AP always posts. Even for
quantity_return, a debit memo equal tobase_total_priceposts to vendor AP.
¶ 5. Data Model (Dev)
Source: tenant schema (tb_credit_note, tb_credit_note_detail, tb_credit_note_comment, tb_credit_note_detail_comment).
¶ 5.1 tb_credit_note
| Field | Prisma Type | Nullable | Description |
|---|---|---|---|
id |
String @db.Uuid |
No | Primary key. |
cn_no |
String? @db.VarChar |
Yes | CRN reference number; unique among non-deleted rows. |
cn_date |
DateTime? @db.Timestamptz(6) |
Yes | Document date — drives FX rate resolution. |
doc_status |
enum_credit_note_doc_status |
No | draft → in_progress → completed / cancelled / voided. |
credit_note_type |
enum_credit_note_type |
No | quantity_return or amount_discount. |
vendor_id, vendor_name |
String? @db.Uuid / VarChar |
Yes | Snapshot from tb_vendor at draft. |
grn_id, grn_no, grn_date |
mixed | Yes | Anchor GRN — required for quantity_return, optional for amount_discount. |
pricelist_detail_id, pricelist_no, pricelist_unit, pricelist_price |
mixed | Yes | Optional pricelist reference. |
currency_id, currency_code, exchange_rate, exchange_rate_date |
mixed | Yes | Currency snapshot + FX rate on cn_date. |
cn_reason_id, cn_reason_name, cn_reason_description |
mixed | Yes | FK + snapshot to tb_credit_note_reason. |
invoice_no, invoice_date, tax_invoice_no, tax_invoice_date |
mixed | Yes | Vendor's credit-invoice reference for AP matching. |
workflow_id, workflow_*, user_action |
mixed | Yes | Workflow state (see Section 6). |
last_action, last_action_* |
mixed | Yes | Most recent transition. |
note, description, info, dimension, doc_version |
mixed | Yes | Standard metadata. |
| Audit columns | — | Yes | created_*, updated_*, deleted_*. |
Constraints: @@unique([cn_no, deleted_at]) map creditnote_cn_no_u; @@index([cn_no]). FKs to tb_vendor, tb_currency, tb_good_received_note, tb_credit_note_reason — all onDelete: NoAction.
¶ 5.2 tb_credit_note_detail
| Field | Prisma Type | Nullable | Description |
|---|---|---|---|
id, credit_note_id, sequence_no |
mixed | No / No / Yes | PK, parent FK, ordinal. |
inventory_transaction_id |
String? @db.Uuid |
Yes | FK to originating tb_inventory_transaction for quantity_return. Null for amount_discount. |
location_id, location_*, delivery_point_* |
mixed | Yes | Original receipt location; return sources from same. |
product_id, product_* |
mixed | No / Yes | Product snapshot. |
return_qty, return_unit_*, return_conversion_factor, return_base_qty |
Decimal(20,5) / mixed |
Yes | Return qty in user unit + base. 0 for amount_discount. |
price |
Decimal(20,5) |
Yes | Unit price — typically the GRN line price. |
tax_*, is_tax_adjustment |
mixed | Yes | Tax snapshot + base conversion. |
discount_*, is_discount_adjustment |
mixed | Yes | Discount snapshot + base. |
extra_cost_amount, base_extra_cost_amount |
Decimal(20,5) |
Yes | Allocated extra-cost credit (e.g. freight). |
sub_total_price, net_amount, total_price |
Decimal(20,5) |
Yes | Line totals in transaction currency. |
base_* |
Decimal(20,5) |
Yes | Same in BU base currency. |
info, dimension, doc_version, audit |
— | Yes | Standard metadata. |
Constraints: @@unique([credit_note_id, sequence_no, deleted_at]); @@index([credit_note_id, sequence_no]). FKs onDelete: NoAction.
¶ 5.3 Comment tables
tb_credit_note_comment and tb_credit_note_detail_comment follow the canonical comment shape — see purchase-request/01-data-model.
¶ 6. Workflow / Business Rules
doc_status: draft → in_progress → completed (terminal); cancelled and voided are terminal alternatives.
draft— editable; no GL, AP, inventory effect.in_progress— locked except where the active stage permits; approvers fromuser_action.execute[]per system-config/workflow.completed— inventory posting fires forquantity_return; cost revaluation foramount_discount; AP debit memo for both.cancelled— terminated before completion; no postings.voided— reversal of acompletedCRN within the open period; reverses every posting.
Stage routing, role mapping, and action gating reuse the PO-side workflow definition by default. GRN anchor: return lines are bounded by receipted - already returned on the lot. Authorisation: only users in user_action.execute[] may transition.
¶ 7. Cross-References
- purchase-order — the PO behind the original GRN; CRN totals roll up into PO open/received reporting.
- good-receive-note — anchor for every
quantity_returnline. - costing —
COST_POST_003(amount revaluation),COST_XMOD_006(lot cost reversal),COST_CALC_005(FX revaluation). - master-data/credit-note-reason — reason taxonomy.
- master-data/exchange-rate — dated rate resolution on
cn_date. - master-data/vendor — vendor snapshot and AP debit-memo routing.
¶ 8. References
- Prisma:
../carmen-turborepo-backend-v2/packages/prisma-shared-schema-tenant/prisma/schema.prisma—tb_credit_note(lines 321-397),tb_credit_note_detail(lines 434-508),tb_credit_note_comment(lines 399-432),tb_credit_note_detail_comment(lines 510-543), enumsenum_credit_note_typeandenum_credit_note_doc_status(lines 195-206). - Frontend route:
../carmen-inventory-frontend/app/(root)/procurement/credit-note/. - Carmen docs:
../carmen/docs/cn/— CN-PRD, CN-Business-Requirements, CN-API-Specification, CN-Page-Flow, CN-User-Flow-Diagram.