> ## Documentation Index > Fetch the complete documentation index at: https://docs.arcuserp.com/llms.txt > Use this file to discover all available pages before exploring further. # Match a bank transaction to a posted journal entry > Ties a bank transaction to cash the books ALREADY carry as a posted journal entry that no subledger record explains: a bank fee the feed posted itself, a manual correction, a cutover entry. It is the fifth bank-match verb and the only one that points at the general ledger directly. Posts NO journal entry of any kind. The money is already booked; the defect this closes is that the bank side never said so, which left the line in the review queue offering to book it a second time under a different idempotency key. Atomic: both rows are locked and updated inside one transaction (`matched_journal_entry_id` plus `reconciliation_status = 'matched'`). Refuses an entry that is not posted, that was voided, that has been reversed, or that another bank transaction already claims; refuses a bank line that is excluded, still pending, or already matched. An amount difference is REPORTED as `amount_warning`, never refused: the caller chose the pair. Reversible via the unmatch flow. Requires `accounting:write` scope. Idempotent via the Idempotency-Key header. THE ONE RULE: delegates to the canonical `matchBankToJournalEntry` handler shared with the internal UI. ## OpenAPI ````yaml /openapi.yaml post /entities/{entity_id}/reconciliation/match-journal-entry openapi: 3.1.0 info: title: Arcus ERP Public API version: 1.0.0 description: > Arcus ERP public REST API. Designed for external integrations and data migration. **Authentication.** Bearer token (API key) via the `Authorization` header. Format: `Authorization: Bearer ark_live_ent__` (or `ark_test_*` for sandbox). API keys are issued per-entity in **Settings > Developers > API Keys**. **Entity scoping.** The entity is encoded in the API key prefix; routes are flat (e.g. `/v1/accounts`, `/v1/orders`, `/v1/products`). A small set of platform endpoints (migration, reconciliation, events, webhook endpoints, API keys) use the `/v1/entities/{entity_id}/...` form -- those are noted in their tags. **Key capabilities.** - Related-resource hydration via `?expand[]=` (see `x-arcus-expand` on each resource). - Cursor-based pagination (`starting_after` / `ending_before` / `limit`). - Idempotency via the `Idempotency-Key` header. - Webhook events for asynchronous notification. - Conditional requests / ETag for cache validation. servers: - url: https://api.arcuserp.com/v1 description: Arcus ERP API (accepts both live `ark_live_*` and test `ark_test_*` keys) - url: https://dev-api.arcuserp.com/v1 description: >- Dev sandbox API (test-only data, accepts `ark_test_*` keys against dev RDS) security: [] paths: /entities/{entity_id}/reconciliation/match-journal-entry: post: tags: - Reconciliation summary: Match a bank transaction to a posted journal entry description: | Ties a bank transaction to cash the books ALREADY carry as a posted journal entry that no subledger record explains: a bank fee the feed posted itself, a manual correction, a cutover entry. It is the fifth bank-match verb and the only one that points at the general ledger directly. Posts NO journal entry of any kind. The money is already booked; the defect this closes is that the bank side never said so, which left the line in the review queue offering to book it a second time under a different idempotency key. Atomic: both rows are locked and updated inside one transaction (`matched_journal_entry_id` plus `reconciliation_status = 'matched'`). Refuses an entry that is not posted, that was voided, that has been reversed, or that another bank transaction already claims; refuses a bank line that is excluded, still pending, or already matched. An amount difference is REPORTED as `amount_warning`, never refused: the caller chose the pair. Reversible via the unmatch flow. Requires `accounting:write` scope. Idempotent via the Idempotency-Key header. THE ONE RULE: delegates to the canonical `matchBankToJournalEntry` handler shared with the internal UI. operationId: postReconciliationMatchJournalEntry parameters: - name: entity_id in: path required: true schema: type: string format: uuid - name: Idempotency-Key in: header required: false schema: type: string maxLength: 255 description: Deduplicates retried match submissions for 24 hours. requestBody: required: true content: application/json: schema: type: object required: - bank_transaction_id - journal_entry_id properties: bank_transaction_id: type: string format: uuid description: >- The bank transaction to match. Must be unreconciled, not excluded and not pending. journal_entry_id: type: string format: uuid description: >- The posted journal entry that already carries this cash. Must not be voided, reversed, or claimed by another bank transaction. reconciliation_id: type: string format: uuid nullable: true description: Optional open bank-reconciliation to attach the match to. responses: '200': description: Match recorded. No journal entry was posted. content: application/json: schema: type: object properties: bank_transaction_id: type: string format: uuid journal_entry_id: type: string format: uuid entry_number: type: string nullable: true matched: type: boolean entry_bank_net: type: number description: >- The entry's own signed net across this entity's bank GL accounts, read from the ledger. Comparable to the bank line's signed amount. amount_warning: type: string nullable: true description: >- Set when the bank amount and the entry's bank net differ by more than half a cent. posted_journal_entry: type: boolean description: Always false. This verb records a link and posts no GL. '400': $ref: '#/components/responses/Error' '401': $ref: '#/components/responses/Error' '403': $ref: '#/components/responses/Error' '404': $ref: '#/components/responses/Error' '409': $ref: '#/components/responses/Error' '422': $ref: '#/components/responses/Error' security: - ApiKeyAuth: [] components: responses: Error: description: Error response (400/401/403/404/409/422/429/500) content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' schemas: ErrorEnvelope: type: object description: | Canonical error response envelope. All API errors use this shape. required: - error - code properties: error: type: string description: Machine-readable error key example: not_found code: type: string description: Machine-readable error code (often same as error) example: not_found type: type: string enum: - validation_error - permission_error - not_found - conflict - rate_limit - internal - expand_error - not_implemented example: not_found hint: type: string description: Human-readable one-sentence explanation (English) example: >- The requested order does not exist or does not belong to this entity. param: type: string description: The parameter that caused the error, if applicable example: expand[0] required: type: string description: The scope required (only on insufficient_scope errors) example: accounts:read request_id: type: string description: >- Unique request ID for support tracing (maps to CloudWatch log stream) example: req_abc123 securitySchemes: ApiKeyAuth: type: http scheme: bearer description: | API key issued per entity via Settings > Developers > API Keys. Each key carries scopes (e.g. orders:read, products:write). Bearer token format: Authorization: Bearer ark_live_ent__ Test keys use ark_test_ent__. Both are issued per entity via Settings > Developers > API Keys. ````