> ## Documentation Index > Fetch the complete documentation index at: https://docs.kalshi.com/llms.txt > Use this file to discover all available pages before exploring further. # Amend Order (V2) > Endpoint for amending the price and/or max fillable count of an existing event-market order using the V2 request/response shape. The request `count` is the updated total/max fillable count, equal to already filled count plus desired resting remaining count. This behavior matches the v1 amend endpoints; only the request/response shape differs. Amending a resting order preserves queue position only when the amendment decreases size. All other amendments — like increasing size or changing price forfeit queue position and place the order at the back of the queue. ## OpenAPI ````yaml /openapi.yaml post /portfolio/events/orders/{order_id}/amend openapi: 3.0.0 info: title: Kalshi Trade API Manual Endpoints version: 3.26.0 description: >- Manually defined OpenAPI spec for endpoints being migrated to spec-first approach servers: - url: https://external-api.kalshi.com/trade-api/v2 description: Production Trade API server - url: https://api.elections.kalshi.com/trade-api/v2 description: Production shared API server, also supported - url: https://external-api.demo.kalshi.co/trade-api/v2 description: Demo Trade API server - url: https://demo-api.kalshi.co/trade-api/v2 description: Demo shared API server, also supported security: [] tags: - name: api-keys description: API key management endpoints - name: orders description: Order management endpoints - name: order-groups description: Order group management endpoints - name: portfolio description: Portfolio and balance information endpoints - name: communications description: Request-for-quote (RFQ) endpoints - name: multivariate description: Multivariate event collection endpoints - name: exchange description: Exchange status and information endpoints - name: live-data description: Live data endpoints - name: markets description: Market data endpoints - name: milestone description: Milestone endpoints - name: search description: Search and filtering endpoints - name: incentive-programs description: Incentive program endpoints - name: fcm description: FCM member specific endpoints - name: events description: Event endpoints - name: structured-targets description: Structured targets endpoints paths: /portfolio/events/orders/{order_id}/amend: post: tags: - orders summary: Amend Order (V2) description: >- Endpoint for amending the price and/or max fillable count of an existing event-market order using the V2 request/response shape. The request `count` is the updated total/max fillable count, equal to already filled count plus desired resting remaining count. This behavior matches the v1 amend endpoints; only the request/response shape differs. operationId: AmendOrderV2 parameters: - $ref: '#/components/parameters/OrderIdPath' - $ref: '#/components/parameters/SubaccountQueryDefaultPrimary' requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/AmendOrderV2Request' responses: '200': description: Order amended successfully content: application/json: schema: $ref: '#/components/schemas/AmendOrderV2Response' '400': $ref: '#/components/responses/BadRequestError' '401': $ref: '#/components/responses/UnauthorizedError' '404': $ref: '#/components/responses/NotFoundError' '500': $ref: '#/components/responses/InternalServerError' security: - kalshiAccessKey: [] kalshiAccessSignature: [] kalshiAccessTimestamp: [] components: parameters: OrderIdPath: name: order_id in: path required: true description: Order ID schema: type: string SubaccountQueryDefaultPrimary: name: subaccount in: query description: Subaccount number (0 for primary, 1-63 for subaccounts). Defaults to 0. schema: type: integer schemas: AmendOrderV2Request: type: object required: - ticker - side - price - count example: ticker: HIGHNY-24JAN01-T60 side: bid price: '0.5700' count: '8.00' client_order_id: 8c35ecb3-328f-4f52-8c7c-0f4b9862f8d1 updated_client_order_id: 2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a exchange_index: 0 properties: ticker: type: string description: Market ticker x-oapi-codegen-extra-tags: validate: required,min=1 side: $ref: '#/components/schemas/BookSide' description: Side of the order x-oapi-codegen-extra-tags: validate: required,oneof=bid ask price: $ref: '#/components/schemas/FixedPointDollars' description: Updated price for the order in fixed-point dollars. x-go-type-skip-optional-pointer: true count: $ref: '#/components/schemas/FixedPointCount' description: >- Updated total/max fillable count for the order. Set this to the order's already filled count plus the desired resting remaining count after the amend. x-go-type-skip-optional-pointer: true client_order_id: type: string description: The original client-specified order ID to be amended x-go-type-skip-optional-pointer: true updated_client_order_id: type: string description: The new client-specified order ID after amendment x-go-type-skip-optional-pointer: true exchange_index: allOf: - $ref: '#/components/schemas/ExchangeIndex' default: 0 x-go-type-skip-optional-pointer: true AmendOrderV2Response: type: object required: - order_id - ts_ms example: order_id: 3b23c1c7-f4ef-4f0d-8b9a-9e53c61f1a0d client_order_id: 2a0e3fc9-b593-4aa3-96e5-82f7f7566c2a remaining_count: '8.00' fill_count: '0.00' ts_ms: 1715793690123 properties: order_id: type: string client_order_id: type: string remaining_count: $ref: '#/components/schemas/FixedPointCount' nullable: true x-omitempty: false description: >- Number of resting contracts remaining after the amend. This is the actual post-amend resting quantity, not the request's total/max fillable count. Only present when the amend caused a fill or changed the resting size. fill_count: $ref: '#/components/schemas/FixedPointCount' nullable: true x-omitempty: false description: >- Number of contracts filled as a result of the amend crossing the book. Only present when fills occurred or remaining size changed. average_fill_price: $ref: '#/components/schemas/FixedPointDollars' nullable: true x-omitempty: false description: >- Volume-weighted average fill price for fills resulting from the amend. Only present when fills occurred. average_fee_paid: $ref: '#/components/schemas/FixedPointDollars' nullable: true x-omitempty: false description: >- Volume-weighted average fee paid per contract for fills resulting from the amend. Only present when fills occurred. ts_ms: type: integer format: int64 description: >- Matching engine timestamp at which the amend was processed, as Unix epoch milliseconds. BookSide: type: string enum: - bid - ask description: >- Side of the book for an order or trade. For event markets, this refers to the YES leg only: `bid` means buy YES, `ask` means sell YES. (Selling YES is economically equivalent to buying NO at `1 - price`, but this endpoint quotes everything from the YES side.) FixedPointDollars: type: string description: >- US dollar amount as a fixed-point decimal string with up to 6 decimal places of precision. This is the maximum supported precision; valid quote intervals for a given market are constrained by that market's price level structure. example: '0.5600' FixedPointCount: type: string description: >- Fixed-point contract count string (2 decimals, e.g., "10.00"; referred to as "fp" in field names). Requests accept 0-2 decimal places (e.g., "10", "10.0", "10.00"); responses always emit 2 decimals. Fractional contract values (e.g., "2.50") are supported; the minimum granularity is 0.01 contracts. example: '10.00' ExchangeIndex: type: integer description: >- Identifier for an exchange shard. Defaults to 0 if unspecified. Note: currently only 0 supported. example: 0 ErrorResponse: type: object properties: code: type: string description: Error code message: type: string description: Human-readable error message details: type: string description: Additional details about the error, if available service: type: string description: The name of the service that generated the error responses: BadRequestError: description: Bad request - invalid input content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' UnauthorizedError: description: Unauthorized - authentication required content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' NotFoundError: description: Resource not found content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' InternalServerError: description: Internal server error content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' securitySchemes: kalshiAccessKey: type: apiKey in: header name: KALSHI-ACCESS-KEY description: Your API key ID kalshiAccessSignature: type: apiKey in: header name: KALSHI-ACCESS-SIGNATURE description: RSA-PSS signature of the request kalshiAccessTimestamp: type: apiKey in: header name: KALSHI-ACCESS-TIMESTAMP description: Request timestamp in milliseconds ````