Create a purchase order

Operation ID: createPurchaseOrder

Group: Accounting › Purchase Orders

POST /accounting/purchase-orders

Retry-safe: A write that accepts Idempotency-Key: repeating a request with the same key replays the stored answer instead of executing twice.

Creates a purchase order. The order is created with its lines, and the response contains only its id. The order starts as 'pendingApproval' and then goes through your tenant's approval policy, which approves it at once when no approvers are configured.

Each line is an item line or an expense line, set by isItem. An item line is priced by quantity times price and uses itemId and unitOfMeasureId. An expense line is priced by editableAmount and uses accountId.

Every amount is a plain decimal in the order's currency.

To see the order, including its poNumber, use GET accounting/purchase-orders/:id.

Parameters

Name	In	Type	Required	Description
`Api-Version`	header	string · v1	yes	The API version this request targets, named by its public identifier. Required on every request; omitting it, or naming a version this company does not have, is answered with 400. This document describes version `v1`.
`Idempotency-Key`	header	string	no	An opaque caller-chosen string (1-255 characters) that makes this request safe to retry. Repeating the same key with an identical request body replays the original response instead of re-executing - but only once that original request succeeded; a failed attempt re-executes on retry. Repeating the key with a different body is answered with 422. A key still in flight is answered with 409 - as is a key whose original request was interrupted before it finished, for a few minutes afterwards, until that attempt is presumed dead. A completed response stays replayable for 24 hours. The key is scoped to the caller, not to the action: reusing it for a different action is answered with 409 or 422 rather than treated independently. On read actions this header is ignored. On write actions that cannot offer the guarantee it is answered with `400 IDEMPOTENCY_NOT_SUPPORTED` rather than silently ignored.

Request body

Required, application/json: createPurchaseOrderInput.

Field	Type	Required	Description
`entityId`	string	yes	The legal entity that owns the order. See id on GET base/entities. Example: `"8f2c1d40-5a6b-4c7d-9e80-1f2a3b4c5d6e"`.
`vendorId`	string	yes	The vendor the order is placed with. See id on GET accounting/vendors/:id. Example: `"3b7d5e9c-1a24-4f80-9c6d-2e8f70b13a45"`.
`currency`	string	yes	The currency of the order. Format ISO 4217, for example 'USD'. Governs every line amount. Example: `"USD"`.
`description`	string	no	The description of the order, shown to the vendor. Example: `"Q4 office supplies"`.
`internalDescription`	string	no	An internal description of the order, not shown to the vendor.
`externalMemo`	string	no	A memo printed on vendor-facing documents.
`externalPONumber`	string	no	The reference number this order has in the upstream system.
`paymentTerms`	string	no	The payment-terms code agreed with the vendor, for example 'net30'.
`startDate`	date	no	The date the order starts. Use format YYYY-MM-DD.
`endDate`	date	no	The date the order ends. Use format YYYY-MM-DD.
`needByDate`	date	no	The date the goods or services are required by. Use format YYYY-MM-DD. Example: `"2026-10-15"`.
`requestedById`	string	no	The employee who requested the order. There is no endpoint for it.
`lines`	array<object>	yes	The lines this order places. At least one is required. Example: `[{"isItem":false,"description":"Stationery","editableAmount":"450.00"}]`.
`lines[].isItem`	boolean	yes	Whether this is an item line. True for an item line, priced by quantity times price. False for an expense line, priced by editableAmount.
`lines[].description`	string	no	A description of what is being ordered.
`lines[].itemId`	string	no	The item being ordered. Expected on an item line.
`lines[].accountId`	string	no	The ledger account the line is booked to. See id on GET accounting/accounts/:id. Expected on an expense line.
`lines[].unitOfMeasureId`	string	no	The unit the quantity is expressed in. Expected on an item line.
`lines[].departmentId`	string	no	The department the cost is allocated to. See id on GET people/departments/:id.
`lines[].quantity`	decimal	no	The ordered quantity, as a decimal. Expected on an item line.
`lines[].price`	decimal	no	The unit price, in the order currency, as a decimal. Expected on an item line.
`lines[].editableAmount`	decimal	no	The manually entered line amount, in the order currency, as a decimal. Expected on an expense line.
`lines[].startDate`	date	no	The date this line starts. Use format YYYY-MM-DD.
`lines[].endDate`	date	no	The date this line ends. Use format YYYY-MM-DD.
`lines[].estimatedDeliveryDate`	date	no	The expected delivery date for this line. Use format YYYY-MM-DD.
`attachments`	array<object>	no	Files to attach to the order. Each names an already-uploaded file by its id.
`attachments[].fileName`	string	yes	The display name of the attached file.
`attachments[].fileId`	string	yes	The identifier of the already-uploaded file. There is no endpoint for it.

{
  "entityId": "8f2c1d40-5a6b-4c7d-9e80-1f2a3b4c5d6e",
  "vendorId": "3b7d5e9c-1a24-4f80-9c6d-2e8f70b13a45",
  "currency": "USD",
  "description": "Q4 office supplies",
  "internalDescription": "<internalDescription>",
  "externalMemo": "<externalMemo>",
  "externalPONumber": "<externalPONumber>",
  "paymentTerms": "<paymentTerms>",
  "startDate": "2026-01-15",
  "endDate": "2026-01-15",
  "needByDate": "2026-10-15",
  "requestedById": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
  "lines": [
    {
      "isItem": false,
      "description": "Stationery",
      "editableAmount": "450.00"
    }
  ],
  "attachments": [
    {
      "fileName": "<fileName>",
      "fileId": "3fa85f64-5717-4562-b3fc-2c963f66afa6"
    }
  ]
}

Response

200 Success

Under data (createPurchaseOrderOutput):

Field	Type	Required	Description
`id`	string	yes	The unique identifier for the created purchase order. Example: `"9c4e1b70-8d25-4a63-b19f-5e7c02da3846"`.

{
  "data": {
    "id": "9c4e1b70-8d25-4a63-b19f-5e7c02da3846"
  },
  "diagnostics": [
    {
      "code": "<code>",
      "message": "<message>",
      "severity": "error",
      "path": [
        "<path>"
      ],
      "details": "<details>"
    }
  ]
}

Response headers

Idempotency-Replayed — Present and true only when this response replays a previously stored one for the same Idempotency-Key, rather than reflecting a live execution. Absent on a live response - never sent as false.

Errors

Code	Status
`REFERENCE_NOT_FOUND`	400
`TOO_MANY_LINES`	400
`IDEMPOTENCY_KEY_CONFLICT`	409
`IDEMPOTENCY_PAYLOAD_MISMATCH`	422

Statuses

400 — Invalid request or business failure. Codes: REFERENCE_NOT_FOUND, TOO_MANY_LINES
401 — The request carries no valid access token.
403 — Not authorized
404 — Not found
409 — The Idempotency-Key is still being processed by another request.
422 — The Idempotency-Key was already used with a different request payload.
429 — Too many requests from this client address. The response has no body and no Retry-After header.
500 — Internal server error