openapi: 3.1.0 info: title: Increase Account Numbers Check Transfers API description: Increase is a bank-grade payments and financial infrastructure platform that exposes a single REST API for moving and holding money in the United States. This document models the primary resources of the Increase API - Accounts, Account Numbers, Cards, Card Payments, ACH / Wire / Real-Time Payments / Check transfers, Transactions, Entities, Events and webhooks, Bookkeeping, Card Profiles and Digital Wallets, Lockboxes, and Simulations. It is grounded in Increase's public OpenAPI 3.1 spec (https://api.increase.com/openapi.json) and the Stainless-generated SDKs. Authentication is a Bearer API key. All endpoints are HTTPS REST; state changes are delivered as Events over HTTP webhooks (no WebSocket surface). Requests support idempotency via the `Idempotency-Key` header. This is a representative, not exhaustive, subset of the full API. version: 0.0.1 contact: name: Increase url: https://increase.com license: name: Increase Documentation url: https://increase.com/documentation servers: - url: https://api.increase.com description: Production - url: https://sandbox.increase.com description: Sandbox security: - bearerAuth: [] tags: - name: Check Transfers description: Printed and mailed checks and check deposits. paths: /check_transfers: get: operationId: listCheckTransfers tags: - Check Transfers summary: List Check Transfers responses: '200': description: A list of Check Transfers. content: application/json: schema: type: object properties: data: type: array items: $ref: '#/components/schemas/CheckTransfer' post: operationId: createCheckTransfer tags: - Check Transfers summary: Create a Check Transfer requestBody: required: true content: application/json: schema: type: object required: - account_id - amount properties: account_id: type: string amount: type: integer source_account_number_id: type: string fulfillment_method: type: string enum: - physical_check - third_party responses: '200': description: The created Check Transfer. content: application/json: schema: $ref: '#/components/schemas/CheckTransfer' /check_transfers/{check_transfer_id}: parameters: - name: check_transfer_id in: path required: true schema: type: string get: operationId: retrieveCheckTransfer tags: - Check Transfers summary: Retrieve a Check Transfer responses: '200': description: The Check Transfer. content: application/json: schema: $ref: '#/components/schemas/CheckTransfer' /check_transfers/{check_transfer_id}/stop_payment: parameters: - name: check_transfer_id in: path required: true schema: type: string post: operationId: stopPaymentCheckTransfer tags: - Check Transfers summary: Stop payment on a Check Transfer responses: '200': description: The Check Transfer with a stop payment applied. content: application/json: schema: $ref: '#/components/schemas/CheckTransfer' /check_deposits: get: operationId: listCheckDeposits tags: - Check Transfers summary: List Check Deposits responses: '200': description: A list of Check Deposits. content: application/json: schema: type: object properties: data: type: array items: type: object additionalProperties: true post: operationId: createCheckDeposit tags: - Check Transfers summary: Create a Check Deposit requestBody: required: true content: application/json: schema: type: object required: - account_id - amount - front_image_file_id - back_image_file_id properties: account_id: type: string amount: type: integer front_image_file_id: type: string back_image_file_id: type: string responses: '200': description: The created Check Deposit. content: application/json: schema: type: object additionalProperties: true components: schemas: CheckTransfer: type: object properties: id: type: string account_id: type: string amount: type: integer fulfillment_method: type: string enum: - physical_check - third_party status: type: string enum: - pending_approval - pending_submission - submitting - submitted - pending_mailing - mailed - deposited - stopped - returned - rejected - canceled type: type: string example: check_transfer securitySchemes: bearerAuth: type: http scheme: bearer description: 'Increase API key passed as `Authorization: Bearer YOUR_API_KEY`. Keys are environment-scoped (production vs sandbox). OAuth is also supported for platform / Increase-for-platforms integrations.'